Hollywood Mystery (1934)

A PR man for a low-budget studio comes up with what he believes is the perfect gimmick: to make a gangster picture with a real gangster in the lead role! He convinces a director--a foreigner who doesn't know much about the American gangster scene--to come on board, and they find what they believe to be their perfect leading man when they spot a tough-looking customer knock out a man in a nightclub. It turns out that the "gangster" they picked isn't a gangster at all, but the man he knocked out in the nightclub is. Complications ensue.