A film from 1996, directed by Walter Hill and starring Bruce Willis.
It's about John Smith (Bruce Willis) who gets stuck in a small town near the border, during the Prohibition, because his car broke down.
There are two gangs in the town, who are at war. John Smith gets stuck in the middle, hiring himself out to both gangs at the same time.
A nice film, featuring lots-o-guns, explosions, and even a decent story line.