Originally buried in parts on Earth by Plutonians, with the intent of having people put him together and use him to conquer the universe. The Plutonian's original appearance soon came to be a Native American legend.
Centuries later, Neutro is finally discovered by scientists John Dodge and Doc Banyan and is put together. They are astonished by what the robot is capable of. Eventually, Neutro gains the attention of Group 777, who want to use Neutro to take over the world.
The evil scientists succeed in taking control of the robot, but John and Doc make it their to priority to get him back.