Bat travels to Yuma to give away the bride at a wedding but discovers the girl's murdered fiancée on the way there. After telling the bride, he joins the posse sent to bring the suspected killer, the Yaqui Kid, to justice.
In 1881 on the way to Yuma, Arizona where Bat is giving a friend away at her wedding, Bat sees a dead man hanging by his heels off the road. At Yuma Bat learns the hanging is the trademark of the Yaqui Kid who is half Indian able to pass as a white man but he has never been seen. Later, Bat and the Sheriff learn the dead man is the groom in the wedding Bat so Bat delivers the news to the bride after telling the Sheriff he will participate in the posse after all. The Sheriff has an Indian scout who directs the posse in the direction the Yaqui Kid took. However, Bat tells the Sheriff the scout neglected to tell them there were two riders in boots on shod horses with one much heavier than the other. They trail them to a river where the Sheriff decides to camp. That night while the Sheriff is on guard and the men asleep, a shot is heard followed by the dead Sheriff found hanging by his heels. Bat grabs the scout and washes his face to reveal a white person - the Yaqui Kid - but he escapes... Written by