Hoppy, Lucky and California search for a mine owned by Trudy Pendleton after it was taken from her by thw swindling gambler Ace Gibson. They find the mine and Hoppy fights Gibson over it.
You can now watch Pirates on Horseback online on the following streaming providers in the United States.
| Directing | Lesley Selander | Director |
| Writing | J. Benton Cheney | Screenplay |
| Writing | Clarence E. Mulford | Characters |
| Writing | Ethel La Blanche | Screenplay |
| Production | Harry Sherman | Producer |
| Crew | Russell Harlan | Cinematography |
| Editing | Carroll Lewis | Editor |
| Editing | Sherman A. Rose | Editor |
| Art | Lewis J. Rachmil | Art Direction |
