Knight Duty(1933)

Harry is a hobo, one step ahead of the law. After accidentally foiling a purse snatcher, he cadges a ride on a flatbed truck, is knocked out when a wax figure falls on him during the ride, and is carried into a museum by someone thinking he's another manikin. Inside, it takes him a while to figure out that he's among dummies. Then, two enterprising jewel thieves arrive to steal the museum director's priceless ruby. Cops are on hand as well: when the ruby goes missing, Harry may be the perfect fall guy. Can Harry stay away from the cops, foil the theft, and behave heroically in front of the museum director's daughter, the same woman whose purse he saved that morning?