Adam Stanheigh, a photographer, awakens in a water-filled tub and finds himself in a disused bathroom along with Dr. Lawrence Gordon, an oncologist. Both men are chained at the ankle to the pipes at opposite ends of the room. Lying between them is a corpse in a small pool of blood holding a revolver and a microcassette recorder. Adam and Lawrence discover tapes in their pockets; the men learn from both tapes that Adam must escape the bathroom, while Lawrence must kill Adam before six o'clock, or he'll lose his wife and daughter and be left to die. Lawrence's tape also implies that the corpse between them was a similar victim who shot himself before succumbing to the effects of a poison. They find a bag containing two hacksaws, though neither is able to cut through the chains. Adam breaks his saw and throws it at a mirror in frustration; Lawrence realizes that the saws are meant to be used on their feet.