A baby was found by a Japanese soldier in India during the World War II and taken to his home. The soldier found a tail in the baby's back but kept him at his home as his son. The baby was named Rikiya and had supernatural abilities. One day, Dr. Tategami comes back from India and said that the world will be occupied by "Zero man". When the "Zero man" people scheme to control the earth, Rikiya, a "zero-man" who was raised by human beings, decides to protect human society and fight against his fellow "Zero man."