In the murky waters off the coast of Nigeria, divers were performing the grim task of recovering the bodies of 12 crew members from the Jascon 4, a sunken tug 100 feet below the surface on the ocean floor, when they got quite the surprise.

"We had already recovered four bodies," said Tony Walker, the dive crew's team leader, who was in the control room on the surface in May. "So the anticipation wasn't great that we were going to find anybody alive at that stage."

Then, incredibly, after nearly three days, a survivor emerged.

The survivor - Harrison Okene, the ship's cook - had been in the bathroom onboard the tug just before 5 a.m., when a massive rogue swell capsized the ship. As it sank, Okene scrambled into a cabin and found an air pocket - just a few feet of precious air.

He stayed there for more than 60 hours in utter darkness and in fear of sharks until the dive team found him. He prayed and drank six sodas.

"The diver saw a hand in the passageway and assumed it was another body," Walker told ABC News today. "When the diver reached up to grab the hand, the hand grabbed the diver."

The team used a standby umbilical diving cable to help Okene reach a diving bell, talking him through the treacherous wreck. Okene's ordeal is believed to be the longest anyone has ever survived after being trapped underwater.

"When he surfaced again, he didn't want to go to sea again," Walker said. "He wanted to go back to being a cook in the hotel."