An astronaut exposed to cosmic rays outside of Saturn's rings returns to Earth and begins to melt away. Escaping from the hospital, he wanders around the backwoods looking for human flesh to eat.

A disturbed boy kills his father with his farm tractor and his arm is mangled in the process. He's taken to a mental hospital where he's outfitted with a hook to replace his lost hand and, years later, he's eventually released from the asylum. He returns home to find his mother has remarried, which sets him off on a murderous rampage.