Cruise Ship Passenger Who Fell Off Ship Swam with Sharks for 20 Hours

The man who fell off a Carnival ocean liner and treaded water for 20 hours before being rescued literally swam with sharks and miraculously survived, but there's one big mystery -- how many drinks did this dude consume before going overboard?!?

James Michael Grimes had an amazingly entertaining chitchat Friday on 'GMA,' where he described the harrowing experience last week in the Gulf of Mexico.

He concedes he had been drinking the day of the fall, although he can't remember how much he had. He remembers downing a few, and winning one in an air guitar contest.

The 28-year-old told a family member he was going to the bathroom, and that's the last anyone saw of him. He doesn't remember going to the bathroom, falling off the ship or hitting the water.

The first thing he recalls is that he was in the ocean with no boat in sight. He was actually passed out in the water after the fall. Unreal!

James was treading water in an area known as a feeding ground for sharks, and it appears he encountered at least one. You gotta watch the video and hear how he survived that.

Eventually, he saw a freighter and swam with the little energy had left ... heading toward the vessel. When a Coast Guard chopper lifted him out the water, the first thing he did was warn one of the military guys he was naked!