A fire in the mountains drives a wolf pack into the nearby desert where they terrorize the local residents. The leader of the wolf pack is Lobo, actually a halfbreed (Rin Tin Tin). When the pack is discovered hunting a herd of cows, a posse gives chase. Lobo leaves his pack to lead the posse away. He is injured and found by a local prospector, Dave Weston (Charles Farrell). The prospector nurses Lobo back to health and the two become close friends. Meanwhile, Weston has made a Borax find in the area. His girlfriend May Barstowe (June Marlowe),daughter of a wealthy rancher, is pleased. However, the local chemist, Borax Horton (Pat Hartigan),actually a claim jumper, plans to steal the claim.

• Warner Bros. Pictures
• Rin-Tin-Tin
• Nanette
• Charles Farrell
• June Marlowe
• Heinie Conklin
• Will Walling
• Pat Hartigan