Cheyenne (1947)

Slick gambler James Wylie (Dennis Morgan) is apprehended by the law and given the option to forgo a prison sentence if he poses as a bandit. His mission is to uncover the identity of the Poet, a notorious outlaw who has been holding up bank-owned stagecoaches and leaving verses at the crime scenes to taunt the authorities. James finds time to woo the Poet's lovely wife, Ann (Jane Wyman), who initially cold-shoulders him. But, as a romance develops, they partner up to find the robber.