Ted Donaldson, Margaret Lindsay, Conrad Nagel, Gloria Holden, Robert B. Williams, Addison Richards, Arno Frey, Eddie Parker, Ace the Wonder Dog, Billy Gray, Gary Gray, Lloyd Ingraham, Bobby Larson, Douglas Madore, Ruth Warren
Fearing that his recently-acquired step-mother, Ann Dennis, is competing with him for his father's affections, and saddened by the death of his dog, young Danny Mitchell seeks consolation in the companionship of a ferocious, Nazi-trained police dog, Rusty, brought to the U.S. by a returning WWII-veteran. The step-mother, with tender understanding, eventually wins Danny over while Danny pacifies his new dog.