The documentary uses genuine footage and audio recorded at the time of the accident on the divers'
voice communications equipment and
helmet cameras, supplemented with interviews of several of the individuals involved, as well as some reconstructed footage, to tell the story of the accident. Chris Lemons, along with his colleagues Duncan Allcock and David Yuasa, The vessel's
dynamic positioning system, supplied by
Kongsberg Maritime, failed. This caused the vessel to drift in rough seas, dragging the divers away from the area they were working and eventually snapping the umbilical tether that provided Lemons with
heliox breathing gas, as well as
hot water to heat his suit, power for his light, and a communications link to the bell and surface. He was left with only five minutes supply of breathable gas contained in the emergency gas supply cylinders he carried on his back. For reasons that are unclear to Lemons and his colleagues, but attributed in part to the cold water and having been breathing a gas mix with a high
partial pressure of oxygen, Lemons survived for around 30 minutes while he was located by a
remotely operated underwater vehicle and then by Yuasa, who was able to pull him back onboard the
diving bell. == Release ==