Twenty-eight year old Cotton Pickens wasn't looking for much other than a warm meal when he came to the Wyoming town of Doubtful. But when a shootout with some gamblers shows off his skills with a gun, the residents elect him as sheriff overnight. After accepting the position, Cotton comes face-to-face with a few members of Circle L--led by Big Mike Romain--the gang who roped and dragged the last lawman of Doubtful. Cotton provokes the gang by unhitching the saddle of Rusty and making him drop to the ground, and after a short stand-off, ends up with Rusty as his new deputy. The new deputy informs Cotton of a war brewing amid "The Big Three": Rockinghorse, Circle L and Quartermoon, a trio of ranches that nearly own a million acres between them ... and how only he and Cotton stand against them.