1870 – Somewhere deep in Texas, the rearing of Longhorn cattle from northern Mexico is booming. It has now become a major source of income for the Texan farmers, while at the same time attracting cattle thieves of all kinds.

In Longhorn, the players assume the roles of two particularly feared outlaws: Eagle Perkins and Jessie Artist Byrd. The aim of the game is simple: to steal cattle (and a few gold nuggets, if possible) to see who can amass the most money by the end of the game — or who can get his opponent arrested by the sheriff!