Human cowboy hero is teamed with Rex, King of Wild Horses, an ornery critter but a magnificent animal.
| Actor | Role |
|---|---|
 Jack PerrinPhil Manners / The Lone Rider | Phil Manners / The Lone Rider |
 RexRex, a Horse (as Rex King of the Wild Horses) | Rex, a Horse (as Rex King of the Wild Horses) |
| SStarlight the HorseStarlight, a Horse (as Starlight the Wonder Horse) | Starlight, a Horse (as Starlight the Wonder Horse) |
 Kathleen CollinsMary Ransome | Mary Ransome |
 J.P. McGowanAbner Whitcomb | Abner Whitcomb |
 Cuyler SuppleeOther Man | Other Man |