A freelance photographer, Sara, hires divers, Iván and Edgar, and they head to the open sea in a small motor boat with Drui, a teenager, the pregnant Thais and her husband Victor. When Iván and Edgar dive, Sara sees a man floating adrift and she brings him on board. Soon they realize that the man is dead and the clumsy Victor stumbles and shots the flare in the gasoline tank. The boat explodes and the group tries to swim to the distant coast. Soon they see a cargo ship anchored in the sea and they ask for help. But Sara, Iván and Edgar witness two crewmen stabbing a man and throwing his body overboard. However, they decide to climb the pilot ladder and hide in the ship, expecting to reach a port. When Thais is bitten by a rat, Sara and Victor seek medicine to disinfect her hand, but one crewman sees him. Victor decides to turn himself in to protect the other stowaways. His scheme does not work as planned and the trip has a tragic end.