The Amazing Mr. Malone – The Lucky Stiff. 1947

A security guard dressed in a dark uniform is reaching for his sidearm, which is holstered on his right hip. He stands in front of a brick wall, with his left hand resting on his belt. His facial expression suggests a state of high alertness and readiness to act in case of any threat or danger.
Security Guard Drawing his Weapon --- Image by © Royalty-Free/Corbis "Used with permission from Microsoft."

Arturo is a gambler who is gaining a reputation for being lucky. Soon nobody wants to gamble with him. He has arguments with some in the gambling rings. He calls on Malone when he is threatened, but before Malone can get back to him, he is dead.

Malone follows up on some leads and not only helps the cops get the bad guy, but solve what happened, and who did it.