Based on

Movies like Ambush (1939)

Four bandits swoop down on a California bank and flee with $98,000, leaving a truck as the only clue to their identity. Jane Hartman, bank secretary, recognizes the truck as one on which her brother Charles worked. Fleeing to her brother, she is trapped by the gang, composed of its master-mind, Gibbs, Sidney, a gunman, and Randall, a blackballed airplane pilot. Under threat of bodily harm to her brother, she lures truck-driver Tony Andrews to the hideout, and he is forced to help them in their escape attempt.