A never-before-seen woodsman mysteriously appears aboard a submarine that's been trapped deep under water for months with an unstable cargo. As the terrified crew make their way through the corridors of the doomed vessel, they find themselves on a voyage into the origins of their darkest fears.

John Books an aging gunfighter goes to see a doctor he knows for a second opinion after another doctor told him he has a cancer which is terminal. The doctor confirms what the other said. He says Books has a month maybe two left. He takes a room in the boarding house and the son of the woman who runs it recognizes him and tells his mother who he is. She doesn't like his kind but when he tells her of his condition, she empathizes. Her son wants him to teach him how to use a gun. Books tries to tell him that killing is not something he wants to live with. Books, not wanting to go through the agony of dying from cancer, tries to find a quicker way to go.

The physician's death orphans his two adolescent daughters. Their older brother is able to convert some of the doctor's small estate to cash. But it is late in the day, and with the banks closed he stores the money in his father's household safe. The slatternly housekeeper, aware of the money, enlists a criminal acquaintance to crack the safe. She attempts to get into the adjacent room where the sisters tremble in fear, but finds that the door is locked. The drunken housekeeper menaces them by brandishing a gun through a hole in the wall. But the resourceful girls use the telephone to call their brother who has returned to town. He gets the message and organizes a rescue party.