Cowboy Ross McEwen arrives in town. He asks the banker for a loan of $2000. When the banker asks about securing a loan that large, McEwen shows him his six-gun collateral. The banker hands over the money in exchange for an I.O.U., signed "Jefferson Davis". McEwen rides out of town and catches a train, but not before being bitten by a rattler. On the train, a nurse, Miss Hollister, tends to his wound. A posse searches the train, but McEwen manages to escape notice. However a mysterious Mexican has taken note of the cowboy, and that loudmouthed brat is still nosing around. Who will be the first to claim the reward for the robber's capture?