Synopsis by Hans J. Wollstein
Clark Stuart (Ray Corrigan) manages to avoid the soldier's bullets by hiding on an upper shelf. Accusing the American of being a spy, Dupray (LeRoy Mason) orders him to face a firing squad. Zamorro (Duncan Renaldo) and Macklin (Maston Williams), meanwhile, attempt another raid on the wagon train, but are once again defeated by the Rider's whistling arrows. the Rider (Julia Thayer) and her Painted Stallion also manage to break Stuart out of prison just as Zamorro and his men are abducting the wagon train's gunpowder cart. As Clark struggles with the driver, the wagon explodes.