Deep Dive Mystery: Hit by the Bends

Blue Lake holds a mystery deep beneath its surface. And Martin Robson wants to solve it. The British diver descends into the murky depths. But hundreds of feet underwater, an invisible and excruciating force suddenly overwhelms him. Semi-paralysed and sinking, Martin is only at the start of an extraordinary ordeal - one that will ultimately last not for hours, but days… A Noiser podcast production. Hosted by John Hopkins. Written by Luke Lonergan | Produced by Ed Baranski | Assistant Producer: Luke Lonergan | Script edit by Joe Viner | Exec produced by Joel Duddell | Sound supervisor: Tom Pink | Sound design & audio editing by Jacob Booth, Liam Cameron, Matt Peaty | Assembly editing by Rob Plummer | Compositions by Oliver Baines, Dorry Macaulay, Tom Pink | Mix & mastering: Ralph Tittley. For ad-free listening, bonus material and early access to new episodes, join Noiser+. Click the subscription banner at the top of the feed to get started. Or go to noiser.com/subscriptions If you have an amazing survival story of your own that you’d like to put forward for the show, let us know. Drop us an email at [email protected] Learn more about your ad choices. Visit podcastchoices.com/adchoices

Speaker names marked ? are inferred from speaking time and the show’s known hosts — they are not voice-verified.

• 0:00Speaker 00

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• 1:03John Hopkins?

  It's Friday, January 13, 2012. Somewhere deep within Russia's north Caucasus mountain range.

• 1:11John Hopkins?

  Nestled in a wooded glade, a light fog drifts above Blue Lake.

• 1:17John Hopkins?

  At just 240 by 140 meters, Blue Lake is small and unremarkable. An opaque turquoise pool, surrounded by snow-covered foothills.

• 1:30John Hopkins?

  But beneath the surface, lies a mystery.

• 1:35John Hopkins?

  Every day, 70 million liters flow out of this body of water, feeding nearby rivers and streams. But the lake, never changes volume.

• 1:47John Hopkins?

  That means the same daily volume of water must flow into the lake. But nobody knows where from.

• 1:57John Hopkins?

  One hundred and sixty metres below the surface, British diver Martin Robson is part of a team intent on finding the elusive hidden source.

• 2:08John Hopkins?

  But after scouring the depths for as long as safety will permit, Martin is yet to find a thing, and his exploration window is drawing to a close.

• 2:19John Hopkins?

  Now he has to ascend, slowly, making regular stops along the way to avoid decompression sickness, more commonly known as the bends.

• 2:30John Hopkins?

  Martin begins to swim upwards, kicking his fins as the dark of the deep eerily merges back into the blue light trickling down from the surface.

• 2:41John Hopkins?

  When he reaches sixty metres, he stops.

• 2:45John Hopkins?

  He's expecting to meet his support diver, Andre, who should be delivering bailout cylinders with extra breathing gas.

• 2:53John Hopkins?

  But Andre is nowhere to be seen.

• 2:58John Hopkins?

  Martin checks his gas supply. He should have enough left. So he continues up towards the habitat, a shallow, depth-submerged chamber where he will wait out his final decompression stop.

• 3:14John Hopkins?

  But before he reaches the habitat, a pair of support divers approach from above. Neither of them is Andre.

• 3:22Speaker 03

  I actually asked them, "What's the problem?" And they just said, "Nothing, it's okay, we've just, you know, changed your plan." And so, in other words, "We've decided to be your support divers and everything is okay."

• 3:34Speaker 03

  But I knew something wasn't quite right.

• 3:38John Hopkins?

  Now isn't the time to hang around, so Martin presses on with his new support divers.

• 3:45John Hopkins?

  He reaches the habitat and pulls himself up and into the pressurized chamber.

• 3:54John Hopkins?

  After completing his final decompression, Martin swims to the surface.

• 4:01John Hopkins?

  He climbs up and out of Blue Lake, the crisp mountain air flooding his lungs as he sits on a bench and starts to de-kit.

• 4:11John Hopkins?

  Then, he hears footsteps approaching. He looks up. A member of the team comes over, and in a voice hollow with shock, confirms Martin's hunch that something is indeed very wrong.

• 4:26Speaker 03

  It wasn't till I got out of the water and was sitting on the bench where I used to kit up and de-kit that someone came up and just said, "We've lost Andrei."

• 4:47John Hopkins?

  Never wondered what you would do when disaster strikes. If your life depended on your next decision, could you make the right choice? Welcome to Real Survival Stories. These are the astonishing tales of ordinary people thrown into extraordinary situations, people suddenly forced to fight for their lives.

• 5:09John Hopkins?

  In this episode, we meet professional cave diver Martin Robson. In January 2012, Martin is invited to join a research expedition in southern Russia with the aim of locating the water source of Blue Lake.

• 5:24John Hopkins?

  The mission is proceeding as planned until Martin's support diver, Andrei Radionov, suffers a fatal mishap.

• 5:32Speaker 03

  And then, of course, you think, "Okay, now we need to think about why this has happened and what went wrong." I think the general mood was one of just complete disbelief.

• 5:43John Hopkins?

  With so much still planned, the team take the difficult decision to press on with the expedition.

• 5:50John Hopkins?

  But as Martin, once again, descends into the deep, an invisible menace overwhelms him and disaster threatens to strike twice.

• 6:00Speaker 03

  It felt like I had just been shot in the back and had no control over my legs. They felt heavy, as if I was wearing lead boots. Most people, in a lot of circumstances like that, when things go horribly wrong, they bolt to the surface. If I'd done that, I probably would have been dead by the time I'd actually broken the surface of the water.

• 6:24John Hopkins?

  I'm John Hopkins. From the Noiser Podcast Network, this is Real Survival Stories.

• 6:57John Hopkins?

  It's Thursday, January the 19th, 2012, 12:25pm.

• 7:04John Hopkins?

  Forty miles from the city of Nelschik, hidden within the forested foothills of the North Caucasus Mountains, Blue Lake gleams in the winter sun.

• 7:14John Hopkins?

  To one side of the lake is a visitor's centre. To the east, a narrow, single-track road snakes off into the trees.

• 7:22John Hopkins?

  A gentle fog rolls across the water, towards 50-year-old diver Martin Robson, who sits at the lake's edge.

• 7:30John Hopkins?

  Martin inhales deeply, wrinkling his nose as a now-familiar stench greets his nostrils.

• 7:39John Hopkins?

  To locals, Blue Lake is known as "shereko", or "rotten waters". The presence of hydrogen sulphide, which gives the water its luminous colour, also produces the smell of rotten eggs.

• 7:54John Hopkins?

  Unsurprisingly, few tourists ever make the trip.

• 7:58John Hopkins?

  But Martin is no tourist.

• 8:01John Hopkins?

  A world-renowned cave diver, he's here to lead an expedition to discover Blue Lake's elusive source, a mystery that has baffled geologists for decades.

• 8:13John Hopkins?

  Six days ago, the mission was eclipsed by the tragic death of Martin's support diver Andre. Following the accident, some members of the team decided to go home. But Martin, and a small group of fellow divers and scientists, have opted to stay and complete the expedition.

• 8:31Speaker 03

  We don't want it to finish like this, with sort of like, "Let's pack up and go home." We would like it to finish with some sense of accomplishment. And also, there is some sense of accomplishment whereby we're also doing something as a little memorial, if you like, you know, in memory of Andre.

• 8:51John Hopkins?

  Today, Martin is preparing to descend beyond 200 meters, or 650 feet, deeper than any of his previous dives. It's one last roll of the dice to solve the mystery of Blue Lake. They believe it's what Andre would have wanted.

• 9:11John Hopkins?

  A team, complete with medics and support divers, wait in the dive center on hand should anything go wrong.

• 9:18John Hopkins?

  They look on nervously as Martin, kitted out in his dry suit, fins and breathing apparatus, enters the ice-blue water.

• 9:29John Hopkins?

  Guided by a support rope known as a shot line, he drops into the abyss.

• 9:37John Hopkins?

  The walls of the lake slope inward,

• 9:41John Hopkins?

  narrowing towards a vertical central channel like the middle of an hourglass.

• 9:48Speaker 03

  So now you're just in total darkness. It's completely black, just descending through the darkness, like parachuting, you know, free fall, but not as fast. No visual reference, other than the line in front of you that's disappearing into the darkness. It is for me an amazing feeling, just absolutely wonderful. Just descending there, completely weightless, just disappearing into the depths of the earth.

• 10:16John Hopkins?

  Being alone in unfamiliar places is a feeling that Martin knows well. As the son of a Royal Navy officer, he had a somewhat nomadic childhood. But he spent most of his early years on the island of Mauritius.

• 10:31John Hopkins?

  With his parents often preoccupied, a young Martin was left to his own devices. But solitude was never a problem for the adventurous youngster.

• 10:42Speaker 03

  The thing I remember with the most fondness about being on the island of Mauritius is the fact that I could just go off on my own, sometimes even getting my parents just to drop me, take the car, drop me in the middle of the jungle. I used to do a lot of climbing up mountains on my own. I had no clue where I was, no map, no compass, and I just enjoyed the activity of going somewhere that I hadn't been before, and particularly on my own. And I think that just gave me a sense of being able to function quite well without the need for a lot of support.

• 11:21John Hopkins?

  When he was a teenager, the family left Mauritius for a more settled life in Portsmouth, on the south coast of England.

• 11:28John Hopkins?

  After leaving school at sixteen, Martin fell into a series of dead-end jobs. But late one night, he switched on the TV and suddenly found direction.

• 11:40Speaker 03

  I saw an advert, and basically the advert was people in rigid raiding craft, those with inflatable boats with hard hulls, you know, at high speed across the seas and up the beaches, and people storming the beaches and jumping out of helicopters. And I just thought, that just looks like fun. That just looks brilliant.

• 11:58John Hopkins?

  It was an advert for the Royal Marine Commandos. Right there and then, he decided that was what he wanted to do. He rushed himself down to the Royal Navy Recruitment Centre in Kent, where he passed the initial assessment phase.

• 12:14John Hopkins?

  Shortly after completing his training, the young recruit served in the Falklands conflict.

• 12:20John Hopkins?

  Martin found his cool disposition and clarity of thought served him well during this time, even while missiles fell from the sky.

• 12:29Speaker 03

  It wasn't frightening at all. If one of these things lands on my head, I'm not going to know anything about it. So it will or won't happen. And it's just not quite another day at the office, but it's almost like that. It's just a part of what you're doing.

• 12:48John Hopkins?

  The acceptance of his mortality, of feeling calm in the face of danger, would stay with him long after he left the military, four years later. Something else stuck with him, too.

• 12:59Speaker 03

  When I was in the military was when I did my first dive and did a fair amount of diving when I was serving. And I kept that going after I left.

• 13:11John Hopkins?

  Though he continued to dive recreationally after the Navy, Martin never thought of it as a potential career. Instead, he became a firefighter, scuba diving occasionally as a hobby. Then, on holiday in Malta one year, he was taken cave diving by a local guide. The thrill of exploring underwater caverns was like nothing he'd ever experienced.

• 13:37Speaker 03

  And that basically just really hit a nerve and just ignited a passion in me. So when I got back to the UK, I armed myself with some sort of geological survey maps and headed off to France to basically throw myself into any muddy pond, lake, or river that I could find in the hope of finding some caves.

• 13:58John Hopkins?

  Cave diving became Martin's sole focus. After several years honing his skills and gaining experience, he received his instructor qualifications. He began traveling the world, teaching the art of the deep dive, how to descend and ascend safely, how to hold your nerve under pressure. He soon made a name for himself, which led to various invitations to join expeditions across the globe, including a multinational team of scientists and divers who asked Martin to help them locate the mysterious water source of Blue Lake in southern Russia. He said yes immediately, thrilled to be joining.

• 14:42John Hopkins?

  But along with the excitement comes an awareness of the dangers.

• 14:47John Hopkins?

  From extreme water pressure to freezing temperatures and the ever-present threat of equipment failure, deep diving is riddled with potential hazards.

• 14:57Speaker 03

  I would not take any risks either with myself or with anybody else. But if I'm doing something where I have the opportunity to explore, then you try and set it up so that the risk is as minimized as possible and almost nonexistent. To me, the risk of something going wrong compared to the... And I wouldn't call it a reward because it's not. It's the privilege of seeing something on this planet that no one else had seen up to then. And for that, you might take a chance.

• 15:39Speaker 00

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• 16:09Speaker 04

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• 16:42John Hopkins?

  It's 12:40 PM.

• 16:45John Hopkins?

  Martin is 190 metres underwater, well over 600 feet. This is the deepest dive he has gone on this expedition so far.

• 16:57John Hopkins?

  He's followed a different route to a new part of Blue Lake in an attempt to find the source. He's been told he might see discarded Nazi field artillery sunk to the bottom in this area.

• 17:10John Hopkins?

  But at 190 metres, he sees nothing: no caves, no source, no artefacts.

• 17:17John Hopkins?

  Before his dive, the team decided he would go even deeper, past the 200-metre mark, where the last vestiges of light vanish completely. So Martin aims his headlamp and illuminates a path down. Deeper he goes.

• 17:36John Hopkins?

  With the pressure growing, every 60 seconds at these depths will require an additional 30 minutes of decompression on his way back up to the surface. He soon hits 209 metres, the equivalent of 47 London double-decker buses stacked one on top of another. The pressure is equal to a small car sitting on his chest. But Martin stays calm, composed.

• 18:04John Hopkins?

  At 214 metres, the depth gauge on his watch freezes as the extreme pressure overwhelms the electronics.

• 18:13John Hopkins?

  This is now deeper than he'd planned to go, deeper than anyone has gone.

• 18:19John Hopkins?

  But he can't stop now, because there it is.

• 18:26Speaker 03

  Eventually, the bottom of that part of the lake hove into view and it was just incredible. It was just completely barren, silt-covered rocks. But it was still something very special because no one had ever seen that. So again, felt very privileged.

• 18:45John Hopkins?

  At 214 metres down, Martin's powerful strobe light is a speck in the unending darkness. As he swims, the lake's rocky floor slopes away from him.

• 18:58John Hopkins?

  Cracked and cratered, covered in weedy vegetation that twists in a slow dance, he runs his gloved hand along the surface.

• 19:09John Hopkins?

  It's mesmerizing.

• 19:14John Hopkins?

  But it's not why he's here. And there is still no sign of the all-important source.

• 19:21John Hopkins?

  Time ticks away.

• 19:24John Hopkins?

  After 25 minutes underwater, unfortunately, Martin needs to leave.

• 19:29Speaker 03

  Because of the depth I was at, I didn't spend too long there, but I did have a little swim around and then turned around and navigated my way back to what we call the shot line to make my ascent.

• 19:41John Hopkins?

  It's now 4:05 PM. Martin has been slowly rising through the water for three and a half hours, ascending metre by metre, allowing his body to adjust to the changing pressure with regular decompression stops. He now dangles by the support line, 24 metres below the surface.

• 20:04John Hopkins?

  The sun's rays spill down through the murk. He checks his watch again. Time to move up to his next decompression stop.

• 20:16John Hopkins?

  But then, as he moves, something hits him in the back.

• 20:22John Hopkins?

  Out of nowhere, Martin's spine is being pummeled by a wave of explosions,

• 20:28John Hopkins?

  doubling him over in agonizing pain.

• 20:32John Hopkins?

  He lurches forward, his joints burning, his back cracking and popping. There's no mistaking what this is.

• 20:41John Hopkins?

  It's the bends.

• 20:47John Hopkins?

  Decompression sickness, aka the bends, is probably the greatest peril of deep-water diving.

• 20:55John Hopkins?

  The deeper a dive, the higher the pressure, forcing nitrogen gas to dissolve into the blood and tissues.

• 21:03John Hopkins?

  If a diver rises too quickly, as the pressure decreases, the nitrogen doesn't have time to clear. Instead, it forms dangerous bubbles, somewhat similar to opening a can of fizzy drink inside your veins.

• 21:19John Hopkins?

  Even if a diver accounts for this and takes time to slowly decompress on their way up, allowing the bubbles to disperse, it's still not a totally foolproof system.

• 21:31John Hopkins?

  The damage can cause permanent paralysis, even death. The pain is unbearable, as Martin is now discovering.

• 21:41Speaker 03

  It felt like I had just been shot in the back and my legs just... You know, I had no control of my legs. They felt heavy, as if I was wearing lead boots. They felt strange, as if I had a pair of ice-cold, thick, wet woolly socks on.

• 22:00John Hopkins?

  Martin spins ninety degrees, his legs flopping around like jelly as he violently jolts backwards. He's lost all feeling in his lower half and begins to sink.

• 22:13John Hopkins?

  Semi-paralyzed underwater, he needs to grab hold of something or he will plummet to the lake floor. And if he's unable to swim back up,

• 22:24John Hopkins?

  then his fate will be to bob in the depths, waiting for his air to run out.

• 22:30John Hopkins?

  His hands flail, and in the nick of time, he manages to get a grip on the shot line. He has bought himself some time.

• 22:44John Hopkins?

  Now, as the initial shock recedes, he needs to formulate a plan. But it isn't as simple as just going back to the surface. If he surfaces too quickly, the nitrogen bubbles inside him will expand, causing brain and heart failure.

• 23:01Speaker 03

  Because of the dive I have just done, the surface is not, my friend. Most people, in a lot of circumstances like that, when things go horribly wrong, is they bolt to the surface. It's fresh air. That's where I'm supposed to live, on the surface. I'm not supposed to exist underwater. I need to be on the surface, where I can get some help. And if I'd done that, I'd probably been dead by the time I'd actually broken the surface of the water, and I knew that.

• 23:33John Hopkins?

  He is left with one option.

• 23:35Speaker 03

  The only choice I've got, really, is something that is, in some quarters, not frowned upon, but is actually thought of as being just complete insanity.

• 23:46Speaker 03

  To go back down.

• 23:51John Hopkins?

  It may seem totally counterintuitive, but going deeper might be Martin's only path to survival. In order to remove the bubbles that have just exploded in his spine, he needs to squeeze them back into his tissues. The only way to do that is to increase the pressure. The only way to increase the pressure is to go down.

• 24:15John Hopkins?

  Hopefully, when he descends, Martin will recover some feeling in his legs. He will then be able to ascend again, more slowly, up to the surface, where he can receive re-pressurization treatment.

• 24:29John Hopkins?

  It's a faint hope, but it's all he has.

• 24:34John Hopkins?

  Martin takes one last look at the light on the surface. Up above, he sees two support divers swimming in his direction. He signals to them, trying to let them know his outlandish plan. Then he prepares to let go of the line.

• 24:50Speaker 03

  I signaled. I gave a thumbs-down signal, which means I'm going to descend. And so, I let go of the line, and I just disappeared back into the darkness.

• 25:13John Hopkins?

  It's 4:06 PM, deep below the surface of Blue Lake in southern Russia. Martin sinks like a stone through the gloomy depths. The gases in his body froth and fizz, an agonizing unseen torment. Swimming closely behind him is fellow diver Ramon, who is there to assist in whatever small way he can. Martin looks at the shot line reeling past him as he heads further and further down.

• 25:45John Hopkins?

  But deeper means crushing the bubbles in his spine. Deeper gives him a chance of moving his legs. Deeper is the new hope.

• 25:57John Hopkins?

  When he reaches a depth of 36 meters, Martin pulls on the shot line. At this depth and pressure, he begins to regain some feeling in his legs. His plan seems to have worked. The bubbles must have dispersed sufficiently.

• 26:16John Hopkins?

  He kicks his legs gently, gesturing to Ramon that he's got some sensation back. They take their time. They can't rush this. Ramon pumps some air into Martin's dry suit, providing him with some additional buoyancy before the men signal to each other that they are ready to ascend.

• 26:39John Hopkins?

  Soon, the day's faint light glows from above as Martin nears the surface. He can make out the dark blurry figures of his support team jostling above the waterline.

• 26:52John Hopkins?

  Martin pulls on the line and signals to Ramon that he is ready to approach the habitat. A small, box-like chamber, five meters below the surface, rigged with a seat, communication gear, and a fresh oxygen supply.

• 27:07Speaker 03

  So, in the water, we had a thing called a habitat. So basically, if you take an upturned glass and push it into a bowl of water, the glass won't fill up with water. There'll be an air space in the glass with water underneath it. So basically, I will sit in this dry habitat. The advantage are I can come off my rebreather briefly, and eat, and drink, and communicate with people, and just wait out the decompression in a much more comfortable environment.

• 27:38John Hopkins?

  Martin pulls himself into the habitat.

• 27:42John Hopkins?

  He struggles to his feet, the weight of his gear straining against his weakened legs. Weakened, but working. Crucially, not paralyzed.

• 27:54John Hopkins?

  He slumps down on the hard plastic chair. His exhausted body radiates heat, quickly warming up the small chamber.

• 28:04John Hopkins?

  He takes off his mixed gas rebreather, a device that uses a mixture of oxygen, nitrogen, and helium to help him breathe safely at extreme depths.

• 28:15John Hopkins?

  Then he pulls his pure oxygen mask over his head and inhales the fresh air.

• 28:23John Hopkins?

  It's a sweet release after more than seven hours in the water, hours that have all merged into one long, arduous journey back to the surface.

• 28:34John Hopkins?

  After a few moments, he switches back to his rebreather and closes his eyes to rest, a dull pain pulsing in his back and legs.

• 28:45John Hopkins?

  Hopefully, one last decompression stop will alleviate the symptoms he is experiencing. He just has to wait for the last of the bubbles to wash from his spine.

• 28:58John Hopkins?

  Despite the extreme peril he was in just moments ago, Martin soon dozes off. He's exhausted after hours of exertion. Sleep is a welcome respite.

• 29:11John Hopkins?

  But there is something he doesn't know.

• 29:16John Hopkins?

  The peril is far from over. His plan hasn't worked.

• 29:23John Hopkins?

  The bubbles in his spine aren't dissipating. They're expanding. The pressure slowly building, ready to burst at any moment.

• 29:35John Hopkins?

  It's a few minutes later. Inside the habitat, Martin is dozing gently, his head lolling against the white plastic wall of the submerged capsule. When suddenly...

• 29:49Speaker 03

  The pain of this decompression sickness, of this bend, came back, and it came back, you know, with a vengeance.

• 29:58John Hopkins?

  Martin is jerked from his position, equipment tossed to one side as searing bolts of pain shoot through his lower body.

• 30:08John Hopkins?

  Gritting his teeth, he looks down at his legs shoved out in front of him. He tries to move them, but they won't budge.

• 30:15Speaker 03

  I thought that paralysis would be, you know, your muscles going to atrophy and they're sort of soft and jelly-like. But no, my paralysis was the complete opposite. It was like every nerve in my back was firing, and to say that it was painful was an understatement.

• 30:33John Hopkins?

  Martin rips out his rebreather and pulls his oxygen mask back on over his head. Oxygenating his blood and tissue goes some way towards easing the crazed, cramp-like pain ripping through him. It also gives him some movement back, enough to wiggle his way upright.

• 30:53John Hopkins?

  Through the pain, Martin's experience comes to the fore. There's only one place he knows he can go to to find relief:

• 31:02John Hopkins?

  back to the depths once again.

• 31:06John Hopkins?

  But as the water pressure increases around him, so too does the pressure of the oxygen Martin is breathing.

• 31:14John Hopkins?

  At these depths, the human body cannot cope with such a high concentration of O2. At least, not for long.

• 31:23Speaker 03

  So I put this full-face mask on with oxygen and descended down to nine meters. And now I am clock-watching. I'm clock-watching almost every minute because I am now deeper than the depth at which pure oxygen becomes toxic to the human body.

• 31:41John Hopkins?

  He's not only contending with the bends now, he also has the issue of oxygen toxicity to deal with.

• 31:48Speaker 03

  And the most profound symptom would be a convulsion, followed by you're unconscious. And if you're unconscious underwater, then you're going to die. You're going to drown.

• 32:01John Hopkins?

  His time below is limited like never before. He is stuck between the ultimate rock and a hard place. The bends if he goes higher. Oxygen toxicity as he goes deeper.

• 32:14John Hopkins?

  Another minute passes alleviating some of the pain from the nitrogen bubbles. But it's a risky maneuver. The minutes stack up. He's pushing his luck.

• 32:25Speaker 03

  You start off thinking one minute and then two minutes and then you're getting into 10 minutes and 11 minutes and then up. I'm nearly at 20 minutes and it's how long do I think my body is going to accept this huge insult of very high partial pressure of oxygen?

• 32:42John Hopkins?

  After over 20 minutes, Martin can't risk staying down here any longer.

• 32:48John Hopkins?

  The freezing water temperature is rapidly becoming another critical factor. He is well insulated in his high-tech dry suit, but the cold will eventually penetrate, bringing the risk of hypothermia. And so he swims back up to the habitat, yanking himself into the chamber and collapsing into a heap on the floor.

• 33:11John Hopkins?

  He can't stand up. His legs remain in a state of paralysis.

• 33:18John Hopkins?

  The agony below his waist is now coupled with a sharp pain in his stomach and back. Nerves firing, he battles to pull off his oxygen mask.

• 33:28John Hopkins?

  He tries to focus. How can he remove himself from this cycle? He can't keep going in and out of the water. And with the bubbles still in his spine, he can't just go up to the top. Not yet.

• 33:44Speaker 03

  Obviously by now, everybody knows something has gone horribly wrong and they are doing their very, very best to follow whatever instructions I'm trying to give them to help me because I'm still in a position where if I go to the surface now, I'm quite literally done for.

• 34:02John Hopkins?

  Descending to nine meters isn't enough. In order to sufficiently crush the bubbles to give them a chance of surviving on the surface, he needs to go deeper.

• 34:14John Hopkins?

  He grabs his rebreather and plugs it in. He's got to go back down one final time.

• 34:23Speaker 03

  So I put my rebreather back on. And again, you know, to the surprise of a lot of people, I come out of the habitat and I go back down again and I disappear back down to about 16 metres. And that's going to be, you know, my last pressurisation, if you like, my last squeeze of my body before I try and get back to the surface.

• 34:43John Hopkins?

  Martin waits and waits and waits.

• 34:48John Hopkins?

  Each minute at this pressure crushes those bubbles a little bit more.

• 34:54John Hopkins?

  He takes in some heavy breaths. Then he manages to move his legs, just a little, but enough to give himself a little kick back up to the surface.

• 35:05John Hopkins?

  Though, of course, he must do so slowly, agonisingly slowly.

• 35:10Speaker 03

  I made my way back to the surface from those 16 metres. And it took hours because I came up at the speed of a snail. Because I want to give myself every chance of being alive and in a position where I can receive more treatment.

• 35:35Speaker 00

  Visible puts the ultimate wireless hack in the palm of your hand. With unlimited 5G wireless data and hotspot, designed to keep you connected, powered by Verizon's 5G network. And no contract holding you back. Plans start at $25 a month. Or get the premium Visible Plus Pro Plan and save $10 on your first month when you use promo code HACK. Make the switch at visible.com. Terms apply. See visible.com for details.

• 36:04Speaker 04

  For families facing hunger this holiday, your generosity could mean one less difficult choice. Across the Feeding America network, your gift fulfils the promise of connecting neighbours to nourishing food and stability. This Thanksgiving, give at feedingamerica.org/holiday.

• 36:25John Hopkins?

  Eventually, Martin's hooded head breaches the surface.

• 36:32John Hopkins?

  He flops his torso onto the platform, moonlight now shimmering on his heaving, trembling dry suit.

• 36:41John Hopkins?

  Support divers and medics surround him, but Martin pulls himself up. Slowly, but surely, with pain still thrumming in every fibre of his body, he wobbles to his feet.

• 36:55John Hopkins?

  He shuffles into the dive centre, where a colleague takes him by the hand and guides him to a bench.

• 37:03John Hopkins?

  As he begins to take off his equipment, questions are thrown his way. How is he feeling? What happened? What does he need? But after so long in the water, Martin's immediate focus is actually on his rumbling stomach.

• 37:17Speaker 03

  I've been underwater for a very, very long time, so then, much to everybody's surprise, I stopped and had a bowl of hot soup, something to eat. And then I started to make my way up to the ambulance.

• 37:33John Hopkins?

  Martin shuffles to the waiting vehicle, battling through the pain, and climbs inside.

• 37:41John Hopkins?

  The ambulance speeds towards the nearest hospital in Nalchik, forty miles away.

• 37:47John Hopkins?

  His body is still full of dangerous nitrogen bubbles, blocking blood flow, pressing on his nerves, threatening his brain and spine. He will need an extended stay in a pressurised hyperbaric chamber to slowly and safely reintegrate the nitrogen into his bloodstream. And even then, there's no guarantees. He could suffer lasting paralysis, brain damage, or worse.

• 38:18John Hopkins?

  The ambulance squeals through the snow-covered mountain paths of the North Caucasus, flying around corners and skidding across dirt tracks.

• 38:29John Hopkins?

  Inside, Martin is in excruciating pain. He has bought himself some time, but more suffering was inevitable, and now another attack has hit. His legs have now entered what is known as spastic hypertonia, continual spasms causing agony in his muscles. He twists and contorts on his stretcher.

• 38:52John Hopkins?

  Finally, they arrive at the Republican Clinical Hospital in Nalchik. A cold wind whistles as Martin is pulled from the ambulance and wheeled into the emergency room.

• 39:04Speaker 03

  I'd been led to believe that there was, you know, what we would call, like, proper medical facilities. So when I got to Nalchik, expecting proper hyperbaric facilities, it was basically what we call a one-atmosphere oxygen treatment chamber. Basically, it's just a slightly larger plastic device, slightly bigger than a coffin with a hinged lid, and a kind of like, you know, a Doctor No-type Perspex dome.

• 39:36John Hopkins?

  This isn't right.

• 39:39John Hopkins?

  Martin was under the impression that a fully operational hyperbaric chamber existed near to Blue Lake. The small chamber here in Nalchik isn't fit for purpose. It cannot treat the bends in the way Martin requires.

• 39:54Speaker 03

  And I was put into this thing and, you know, pressurized to one bar of oxygen. Now, oxygen as a therapeutic gas is great, but I needed to be at a much higher pressure. And even after being in this little pod for a little while, you know, there was a bang and a hiss, and I think all the seals failed. And then I was taken out and just put into a hospital ward and just left there, basically. And I just laid in this hospital bed in excruciating pain.

• 40:26John Hopkins?

  It's clear that Martin needs to be taken somewhere with a fully operational hyperbaric chamber. The question is where?

• 40:35John Hopkins?

  His friends and colleagues busy themselves, placing urgent calls far and wide, but the odds are stacked against them. They're in the throes of a bitter Russian winter, stranded in a remote, mountainous location.

• 40:49John Hopkins?

  Wherever Martin needs to be, he's not getting there quickly.

• 40:54John Hopkins?

  Ultimately, it will take the help of a stranger many hundreds of miles away, the involvement of the upper echelons of the Russian government, and time, a lot more time, to save Martin Robson's life.

• 41:17John Hopkins?

  It's about eight hours after Martin arrived at the hospital in Nalchik. He is now out of the small pressurized chamber and in intensive care.

• 41:27John Hopkins?

  His life hangs in the balance.

• 41:30John Hopkins?

  But progress has been made in finding a hyperbaric chamber. His team have contacted 77-year-old Dr. Gennady Sokolov, Russia's foremost authority on decompression sickness.

• 41:44John Hopkins?

  Though he's over 1,800 miles away and now retired, Dr. Sokolov drops his birthday plans to find a way to save Martin's life.

• 41:56John Hopkins?

  With most state-of-the-art hyperbaric chambers hundreds of miles from Martin's location, the main problem is finding a way to move him while keeping him pressurized. To make matters worse, the bad weather has closed airports.

• 42:12John Hopkins?

  Now, eight hours into his hospital stay, death by brain aneurysm, heart failure, or organ collapse could all occur at any moment.

• 42:22John Hopkins?

  Dr. Sokolov uses his contacts. Urgent appeals are made, favors are called in.

• 42:29John Hopkins?

  Eventually, the alarm gets sounded all the way up the chain of command to the very top, the head of the Ministry of Emergency Services. Apparently, having a renowned British diver die on Russian soil is a bad look. One to be avoided at all costs. So, Martin's case gets expedited. He's been made a priority. The Ministry enlists the help of the Southern Regional Search and Rescue Team, based in Sochi, around 350 miles away. They swiftly assemble their hyperbaric life raft, known as the DART, a movable chamber that resembles an astronaut's space module. The DART is attached to a huge transporter aircraft.

• 43:15John Hopkins?

  They will carry him from an airport to a recompression chamber in Sochi. They're granted special dispensation to fly.

• 43:26Speaker 03

  So eventually, I get taken from the hospital to an airport. The ambulance driver was given the instructions on driving from Nalchik to this airport, to drive quickly. You've got to drive like a bat out of hell. So he did, and it was comical because, you know, the back doors of the ambulances are open. You know, we lost some stuff out the side door. I thought I was going to disappear on my stretcher down the high street. You know, it's like, because he was driving like a maniac.

• 43:54John Hopkins?

  Martin arrives at the airport in one piece, is loaded into the DART and flown to Sochi, where the hyperbaric chamber awaits.

• 44:04John Hopkins?

  By the time he arrives and meets Dr. Sokolov, it's been 29 hours since the bends hit.

• 44:11John Hopkins?

  The doctor explains that he has calculated that Martin will need to be in the chamber for an excruciating nine days.

• 44:20John Hopkins?

  It's the only way to save him. And so Martin enters the pressurized capsule. Its walls laden with equipment and dials.

• 44:31John Hopkins?

  It's his new home and his last chance of escaping the worst consequences of the bends.

• 44:38Speaker 03

  The door is shut with just myself and a medical technician called Dennis. They have to have someone in there with me. And the door is shut and they start to pressurize me on the start of a very, very long and occasionally uncomfortable journey back to the surface.

• 44:57John Hopkins?

  Slowly, over the 216 hours, Martin can do nothing but sit and wait. It's an arduous and often painful experience, but having endured so much already, he somehow finds the strength to battle through.

• 45:13John Hopkins?

  He even manages to maintain an optimistic outlook despite the grim prognosis.

• 45:18Speaker 03

  At no point did I think I would ever die. Everybody else thought that. I was the only person who was fairly convinced that everything's going to be okay. And it wasn't this like mindless optimism. It was more like it was an absolute determination. This is not going to end badly. It is going to be fine. And so there's a, there's a sense of almost like closing out thoughts that are irrelevant and are not going to help and working on things that will help. Dr. Sokoloff said, who is this human being? Because he obviously realized that this is not someone who's just going to lay down and die. And I had no intention of doing that.

• 45:59Speaker 00

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• 46:29Speaker 04

  For families facing hunger this holiday, your generosity could mean one less difficult choice. Across the Feeding America network, your gift fulfills the promise of connecting neighbors to nourishing food and stability. This Thanksgiving, give at feedingamerica.org/holiday.

• 46:48John Hopkins?

  After more than a week in the chamber, and ten days since decompression sickness hit under the water of Blue Lake, Martin walks out of the door of the hyperbaric chamber, alive and well.

• 47:02John Hopkins?

  His colleagues and Dr Sokolov greet him with beaming smiles. The bubbles have dispersed, the bends have gone. Finally, he is back on the surface.

• 47:17John Hopkins?

  One of Martin's friends and fellow divers, Mike, steps forward with his arm spread wide. Martin grins.

• 47:25Speaker 03

  It was emotional because I was only there because of everybody else. And Mike had asked me, he said, "I know you're English, and that you don't do these things." He said, "But when you come out, you're going to have to hug everybody. You understand that?" I said, "Yeah," I said, "but I'll only do this on one condition." He said, "What's that?" I said, "I'll come out, I'll have a proper shower, I'll go back in, and then I'll come out again, a little bit more human. And then we can do the filming, and I'll do all the hoax." And that's what we did, and it was, it was very emotional.

• 48:04John Hopkins?

  After Martin returns home, his desire to get back into the water never wavers. He hits the gym, building his strength back up to continue pursuing his passion.

• 48:15John Hopkins?

  Six years later, in 2018, he returns to Blue Lake. He visits the memorial that has been built there for Andre, and returns to the scene of his own near-death.

• 48:28John Hopkins?

  Ultimately, Martin puts his survival down to two crucial factors.

• 48:33Speaker 03

  The unselfishness of other people, and my own determination. When the wheels come off, to be able to focus on what needs to be done. Someone said to me, "You lose a shoelace, it's like your world is ending." "If your house blew up, it would be fine, because you'd be able to cope." It's that kind of thing.

• 48:57John Hopkins?

  In the aftermath of his ordeal, Martin's perspective has shifted.

• 49:02John Hopkins?

  Before, he says, he used to be closed off to others, fiercely independent, reliant on nobody but himself. That's no longer the case.

• 49:14Speaker 03

  Trying to look at people sort of perhaps more open-mindedly and to give other people more time, more of myself to them, almost like to pay it forward because you don't know what's going to happen in the future. So it's definitely sort of opened my eyes to the nicer parts of human behaviour.

• 49:45John Hopkins?

  Next time on Real Survival Stories, we journey deep into the Amazon. In 2002, Dave Boyer heads to Brazil to explore the largest tropical rainforest on Earth. It's a place of breathtaking beauty and constant sensory stimulation.

• 50:04John Hopkins?

  But here, just one wrong step can lead to calamity.

• 50:10John Hopkins?

  When Dave and his travel companion Crystal stray from the trail, they realise that once you're lost in the Amazon, you might never be found.

• 50:19John Hopkins?

  The pair will have to battle downpours, darkness and despair in a slow torture that goes on for days.

• 50:31John Hopkins?

  That's next time on Real Survival Stories. Listen today without ads and without waiting a week by subscribing to Noiser Plus.

• 50:39Speaker 00

  Visible puts the ultimate wireless hack in the palm of your hand. With unlimited 5G wireless data and hotspot, designed to keep you connected, powered by Verizon's 5G network. And no contract holding you back. Plans start at $25 a month or get the premium Visible Plus Pro Plan and save $10 on your first month when you use promo code HACK. Make the switch at visible.com. Terms apply. See visible.com for details.

• 51:08Speaker 04

  For families facing hunger this holiday, your generosity could mean one less difficult choice. Across the Feeding America network, your gift fulfils the promise of connecting neighbours to nourishing food and stability. This Thanksgiving, give at feedingamerica.org/holiday.