British diver revealed what he was thinking when stuck 300ft underwater with no oxygen for more than 30 minutes

A British diver has explained what was going through his mind when he realised he was stuck 300 feet underwater with no oxygen.

Saturation diver Chris Lemons was left fighting for his life after fixing a pipe below the North Sea, near the Huntington oil field off Aberdeen on 18 September 2012.

Due to a positioning system failure, the Bibby Topaz support vessel drifted into rough seas, and Lemons' lifeline to the surface - an umbilical cable which tethered him to the diving bell and the boat - was cut off.

The Scotsman was left in complete darkness, only with a limited emergency gas supply in its backup tanks, estimated to last around five minutes.

On what he was thinking in that moment, Lemons explained to The Guardian: "I was at an exciting point in my life: early thirties, getting married the following year, we were in the process of building a house...

"I had all the hopes and dreams you have at that stage – of children, travel – and it felt as if all of that was about to be ripped away in this strange, lonely, ethereal place.

"I grew up in a middle-class family on the outskirts of Cambridge, and I remember thinking: 'How is this dark, lonely place where I end my days?'."

Lemons accepted his fate (Dogwoof)

With time running out, Topaz launched a remotely operated vehicle (ROV) to locate his whereabouts.

The mini submarine had a camera attached to it, showing Lemons lying on top of the structure in the foetal position.

When he lost consciousness, Lemons said the 'actual moment was peaceful'.

"I feel like a bit of a charlatan. I still get contacted all the time by people who’ve lost loved ones, but I don’t have the right to tell you what it’s like – I didn’t die," he added.

Thankfully, the dynamic positioning system was up and running again, just in time to save Lemons.

Lemons' heroic colleagues managed to track him down and rescue him (Dogwoof)

With just minutes left of emergency gas, colleagues Duncan Allcock and Dave Yuas were able to drag him to safety.

When they got him back into the bell and took off his helmet, Lemons was bright blue.

Allcock then gave him mouth-to-mouth and incredibly, he survived.

"They’re the real heroes in this story," Lemons added: "And everyone on the boat. I’m just a damsel in distress."

While experts still don't know how he made it, Lemons reckons the freezing conditions saved him.

"But I’ve learned that if my body had been so cold that I’d gone into some kind of hibernation or stasis, there is no way Duncan would have been able to resuscitate me that quickly," he said.

Lemons' life-changing experience was the subject of 2019 documentary Last Breath and has been dramatised in 2025 feature film of the same name, directed by Alex Parkinson.

Finn Cole stars as Lemons, while Woody Harrelson and Simu Liu play his fellow divers.

Last Breath will be released in UK cinemas by Entertainment Film Distributors on March 14, 2025.