>> they were in big trouble. the boat was actually beginning to sink rather rapidly. >> alex stewart, an experienced rescue diver, is lowered down from the chopper. >> when they placed me on the board, i had about two seconds. and then, whoosh, i was off it. >> alex knows there's very little time. >> i shouted to tina to get into the water and for her husband to go in the dinghy and to get away from the sinking boat. >> tina doesn't want to get in the water for fear she'll lose hold of priscilla. but then a wave hits the cockpit and the dog falls in to the ocean. she sees alex and paddles toward him. >> we were out in the middle of the ocean. how did this dog get here? and i thought, oh, yeah, here's an added problem to the scenario. >> alex's first priority is rescuing tina and paul. he swims with priscilla back to the boat and focuses on tina. meanwhile, priscilla is fighting