Lobo, wolfdog leader of a wolf pack, has a price on his head. One day suffering from a thorn in his paw, he is found by Dave Weston, a borax prospector and befriended. The animal returns love and loyalty. Later Lobo saves Dave from attacks of scheming villain William 'Borax' Horton, who has designs on Dave's claim. Once again the villain attacks the young prospector and leaves him for dead on the site of the claim. Lobo arrives and Dave sends him with a message to town for help. In the meantime a posse is hunting Lobo, but he manages to escape them and at the same time, decoy them to Dave. There, they learn that Lobo is man's best friend.
Cast
Rin Tin Tin as Lobo
Nanette as Lobo's Mate
Charles Farrell as Dave Weston
June Marlowe as May Barstowe
Heinie Conklin as Alkali Bill
Will Walling as Sam Barstowe
Pat Hartigan as William 'Borax' Horton