A reaction-based shoot-em-up in which the player takes on the role of a gun-slinging Deputy, who has been charged with protecting the town bank from outlaws.

Each stage contains twelve numbered doors, with three doors visable on-screen at any one time. The player must scroll the screen left or right to bring other doors into view. At regular intervals, one or more doors will open to reveal either a bank customer or an outlaw. The customers must be allowed to deposit their money unharmed while the outlaws must be shot before they have a chance to shoot the deputy. Some of the outlaws must be shot twice before they are killed. If the players kills an innocent citizen, a player life is lost.

Doors will only open when they are on-screen and a level is only completed once cash has been deposited safely into the bank via each of the twelve doors. Each level has a tight time limit so it's important to ensure that the player reaches the doors that are about to be opened as quickly as possible. Imminent visitors are indicated by the presence of a bar graph that sits above each door, with a red marker indicating an approaching customer or robber.

In addition to the outlaws, players must also be wary of time bombs that occasionally appear on one of the doors; this is indicated by both a timer and an icon above the door with the bomb. The bomb must be reached and shot before the timer runs out. As well as the outlaws and customers, a small, bandy-legged cowboy occasionally appears holding gifts above his head, these can be shot for bonus points.