Sûpâ jaiantsu (1957)

Foreign power mongers, members of Merapolia Labs, plan to inundate the Earth with mass nuclear destruction. The Emerald Planet council, worried that radiation from Earth could make it to their planet, send Starman to defend Earth's people. Starman has a radiation-detecting watch to help him find the bombs and those behind them. This leads him to save a troubled airliner that is carrying one of the gang as a passenger. After the plane lands in Japan, he intercepts the culprit as he is picked up at the airport. The foreign agent pulls a gun on him but to no effect. The car is stopped, they climb out, and Starman overcomes them. A group of children watching the fight pick up a gun and satchel that are tossed aside during the tussle. One of the children falls while fleeing and is captured. Starman tracks down the kids and asks for the briefcase. He bends the gun into an unusable shape. Going back to his watch, he tracks the car driver to the lab. The driver is rebuked by his superiors for letting Starman disrupt the delivery of important documents. He is tossed in a locked cell where Starman finds him. Starman asks for his cooperation and is obtaining it when a guard sees him and rings the alarm. The driver in killed in the hail of bullets that fly. Starman learns that one of the children was captured. He discovers he is with the agent on a train. He quickly flies to the train, knocks out the agent, and reassures the boy he's alright now. The power mongers are ready to continue their project. Part 1 of a two-part story.