Flint McCullough's involvement in a horse-stealing operation proves that he's ""gone bad."" Reluctantly, Chris Hale sentences him to 20 lashes and permanent banishment from the wagon train. Bill Hawks refuses to flog his friend so the punishment's administered by Sgt. Oakes from nearby Fort Henderson. Hawks soon learns that Flint's uncharacteristic behavior is part of a plan to infiltrate the gang of notorious outlaw, Angel de Muerte. Flint now travels to the ranch of Sam Upton and his sister Madge, a place rumored to have ties with Muerte. The fresh welts on Flint's back persuade Sam to take Flint to meet Muerte, but Flint soon realizes this bearded man is a stand-in for the real Muerte -- none other than Sam Upton himself. While taking Upton to Major Hansen at Fort Henderson, the outlaw dies in an escape attempt. Flint decides to split the $10,000 reward money with Madge Upton who was unaware of her brother's dual identity.