Jack, an American lawyer working in Tokyo is having an affair with Yuri, the wife of a valued client. Yuri is afraid that her husband Eiji knows. When Eiji's account develops a crisis, Jack finds both Eiji and Yuri about to embark on a day trip at sea. Eiji insists that Jack join them aboard their cabin cruiser, but Jack fears the husband's motives and dreads the ocean since he lost his younger brother to the sea 25 years ago. Because of Yuri, and his responsibility to his client, Jack reluctantly accepts. But when they sail from the Tokyo Bay into the open sea, this trip turns to terror, and the ocean has a terrible destiny for each.