La dernière plongée de Dave

Two high level scuba-divers and long-time friends, broke a world record for depth in the Boesmansgat cave in South Africa. It would take them 15 minutes to reach the bottom, but 12 hours to surface. Having reached the bottom, against all odds, they find a body. They decide to come back and retrieve it. They call the parents, enroll fellow divers, and hire a cameraman to document the dive. Little did they know that on that historic dive, one of them would not be coming back.