1943 film by Miguel M. Delgado, Fernando de Fuentes

1933 film by Fernando de Fuentes

Insurance detective Steve Hastings is sent by his company to investigate the disappearance of a fellow agent. His first lead is the agent's fetching sister, Victoria, whom he trails to Mexico City. After charming his way into her confidence, Steve helps Vicki unravel the mystery.

Cantinflas, the boyfriend of the servant of a rich industrial man, gets into the house in order to kill a mad dog. Suddenly this man appears so the servant tells him that Cantinflas is his wife's brother (Leonardo), who had been lost for years. The rich man then remembers that his father in law's testament could only be paid when all brothers get together, so treats Cantinflas, a real bum, as a king.