When Milo Ryder retires as US Marshal, he moves to Purgatoire Valley in Colorado to seek peace and spend more time with his wife, Hannah. But trouble erupts when a horse carrying Gentry Soyer wanders onto the ranch. Gentry nearly falls from his saddle and is bleeding from a gunshot wound to his chest. Not able to leave the incident alone, Milo looks for the men responsible. Will finding a resolution to this mean the end of his working as a US Marshal? Or will he continue to pursue the law when he discovers mysterious men watching his ranch and cattle?