You are in 1930s Chicago and the Mafia rules supreme! Prohibition is in full swing and the gangsters are armed with machine guns. You are the only person who can save the city from their racketeering as an incorruptible detective.

The principle is very simple. Targets appear on three windows on the screen. The (4), (5) and (6) keys are used to shot on each of the targets. But you only have three lives so you must shot the targets quickly and you have to complete a number of different missions in a limited time. You an score extra points in the bonus round every five levels. Then every 10 levels, you have to shoot a boss!