When his master is attacked and left speechless, Ranger is held responsible. On the lam from the Law, the canine hero links up with telegrapher Bill Brady and Bill's girlfriend Helen Meadows. He gets a chance to clear his name by helping Bill trap a pair of outlaws who plan to blow up a mail train and abscond with the loot.
| Actor | Role |
|---|---|
| RRanger the DogRanger | Ranger |
 Helen FosterHelen Meadows | Helen Meadows |
 Rex LeaseBill Brady | Bill Brady |
 Alfred AllenHenry Jordan | Henry Jordan |
 Harry TenbrookMike | Mike |
 Bruce GordonEd | Ed |
| SSpencer Bell'Snowball' Black | 'Snowball' Black |
| VVictor AllenSheriff | Sheriff |