The story of a boy, a dog, and a man. The boy discovers he is heir to a shipping line, and travels to Los Angeles, accompanied by inventor/radio operator Bob Whitlock and Irene Blaine. Their journey is aided by Pal, a wolf dog.
| Actor | Role |
|---|---|
| RRin-Tin-Tin Jr.Pal | Pal |
 Frankie DarroFrank Courtney | Frank Courtney |
 Boots MalloryIrene Courtney | Irene Courtney |
 George J. LewisBob Whitlock | Bob Whitlock |
 Henry B. WalthallJim Courtney | Jim Courtney |
 Hale HamiltonNorman Bryan | Norman Bryan |
 Fred KohlerJoe Stevens | Joe Stevens |
 Niles WelchMason | Mason |
 Gordon De MainMurphy | Murphy |
 Yakima CanuttBill | Bill |
 Cornelius KeefeJerry Patton | Jerry Patton |
 Tom LondonBrooks | Brooks |
 Stanley BlystoneLang | Lang |