Kit Cardigan seeks the killer of his father...among other plot threads leading up to the famous historical incident.

Hanson is using Bobby's carrier pigeons to receive messages. His man Slim shoots them down before they reach Bobby. When Slim is injured, Ranger Daniels posing as a drunk gets the job. He misses the next pigeon on purpose and gets the message from Bobby. But his identity has now become known and the gang rides to get him.

Sent by the Army, Andy Thomas poses as a renegade to find out who has been harassing the wagon trains.