A gang of horse thieves are able to operate because the crooked local sheriff is in cahoots with them. When Tom Mix's beloved horse Tony Jr. is stolen, he steps in to break up the gang.
| Actor | Role |
|---|---|
 Tom MixTom Munroe | Tom Munroe |
| NNaomi JudgeNorma Laird | Norma Laird |
 Arthur RankinBernie Laird, known as 'Little Casino' | Bernie Laird, known as 'Little Casino' |
 John St. PolisColonel Charles Ormsby | Colonel Charles Ormsby |
 Frank BrownleeSheriff Judell | Sheriff Judell |
 Raymond HattonLucky Dawson | Lucky Dawson |
 Francis McDonaldTad McPherson | Tad McPherson |
 Bob KortmanTim McPherson (as Robert Kortman) | Tim McPherson (as Robert Kortman) |
 Lafe McKeeShay | Shay |