Warner Baxter, sporting a black mustache and a musical-comedy Mexican accent, stars as the Cisco Kid, the "Robin Hood of the Old West" created by O. Henry. Edmund Lowe co-stars as Cisco's "friendly enemy" Sgt. Mickey Dunne, the role that was originally to have gone to Raoul Walsh. Both men are madly in love with dusky beauty Tonia Maria (Dorothy Burgess), and in fact Cisco is so "far gone" that he composes a song in the girl's honor (actually, "My Tonia", first heard during the opening credits, was written by Fox studio tunesmiths Lew Brown, B.G. DeSylva and Ray Henderson). Alas, Tonia ends up betraying Cisco to Sgt. Burke. But the crafty, cold-blooded Cisco arranges for Tonia to be killed in the trap set for him (this plot resolution is faithful to O. Henry's original conception of the Cisco Kid, who wasn't really meant to be a "good guy").
by Hal Erickson synopsis