Girl looking for father who disappeared years before in a jungle, finds herself battling greedy civilized people and savages alike.

Western settlers are being driven off their homesteads and ranches by a combination of Indian raids and attacks by bands of mysterious outlaws. The government sends out famed Indian scout Kit Carson and army officer David Brent to investigate, and Carson discovers that a villain named Pegleg controls an outlaw gang called the Black Raiders, and is using them and the Indians to drive out the settlers so he can establish his own empire. He determines to set a trap to expose the identity of Pegleg while avoiding traps and ambushes that Pegleg is setting for him.

Filmed in the Sierra Nevada mountains near Sonora, California, this Universal serial is Universal's 40th sound-era serial. Eagle Scout Bruce Scott, leader of Martinsville Troop Number One, and his pack sets off in search of lost treasure and finds adventure.

Larry Munro has discovered a vein of platinum on his ranch. A group known as the Secret Seven has learned about it and plan to get the Munro Ranch. Kentucky Wade and his friends arrive to help Larry and are soon fighting off attempts on their lives by the henchman of the Secret Seven and the Indians they enlist by bribing them with rifles.

An expedition arrives on an uncharted jungle island to rescue the local natives, led by a jungle boy, from a volcano that is about to erupt.