The Black Rebels Motorcycle Club ride into the small California town of Wrightsville, eager to raise hell. Brooding gang leader Johnny Strabler takes a liking to Kathie, the daughter of the local lawman, as another club rolls into town.
Dardo, a Robin Hood-like figure, and his loyal followers use a Roman ruin in Medieval Lombardy as their headquarters as they conduct an insurgency against their Hessian conquerors.
