A woman marries the fiancé of her late sister but begins to have doubts when he starts to get overly friendly with a former classmate.

After Tokyo police officer Yokoda is killed in the line of duty, his chief decides give Yokoda's body to Dr. Tani for use in a secret scientific experiment: Yokoda's brain will be transplanted into a super-powered robot body, making him into an unstoppable policeman of the future. The supercop develops problems, however, when he begins to remember his human past. Then there is the matter of Dr. Tani's other cyborg, who has become a super-powered homicidal maniac.