 Larry Baker and his vainglorious wife Margaret plan to steal the $200,000 Mohar Gem Collection. They abduct courier Larew Merced from his room and imprison him in a car trunk after they learn that he does not have the gems in his possession. They learn from Merced s papers that a "package" is waiting for him at the railway express office. The manager of the Sunset Motel reports the abduction and Dan Mathews and Sergeant Williams learn of the package themselves when they search Merced s room. They stake out the express office and watch as Baker impersonates Merced to claim the package. They follow at a safe distance, waiting patiently for the right moment to arrest the Bakers and rescue the injured Merced.