U.S. Marshal Chance Thorn gets an assignment to solve the problem of a fifty thousand dollar train robbery of Treasury one hundred dollar bills somewhere outside of Sacramento, California. Chance, home based in San Francisco, gets to Sacramento and digs into the case. It soon develops into much more than a mere train robbery and he is head over six-gun into a counterfeiting scheme that has netted the gang hundreds of thousand of dollars. It’s his job to find the stolen money and now to close down and prosecute the counterfeiters. It’s a double mystery that he has to work hard trying to solve.