The female leader of an international crime ring steals a valuable artifact that can give her the power to control men's minds. Federal agents are dispatched to get it back and stop her evil plans.

The Daily Clarion hires detective story writer Steve Colt to investigate the deaths of a group of scientists working on an atomic rocket development project. Behind the killings is fortune teller Sombra, a spy from an Asian country intent on world domination, who is determined to pilfer the atomic rocket by luring workers from the project to her parlor and killing them with black widow spider venom when they refuse to cooperate.

Knowing the railroad is coming, Carter is after the rancher's land. Bob and Chito return just in time to save Banker Stockton and his money from Carter's men. When Stockton then lends the ranchers money, Carter has them burned out. Bob knows Carter is responsible and when Carter's henchman Saunders is recognized, Bob goes into action.

A society sleuth rescues a kidnapped woman, then is framed for murder.