A crooked mine owner attempts to hijack his rival's shipment of ore, but Helen foils his plot by jumping onto the engine and pulling the throttle wide open, eventually exposing the unscrupulous villain.
| Actor | Role |
|---|---|
 Helen HolmesHelen | Helen |
 Leo D. MaloneyTom Walker - Owner of the Hope Mine | Tom Walker - Owner of the Hope Mine |
 George A. WilliamsWilliams - Owner of the Boss Mine | Williams - Owner of the Boss Mine |
| RRex DownsEvans - Williams' Foreman | Evans - Williams' Foreman |
| NN.Z. WoodMerkey - President of the Smelter | Merkey - President of the Smelter |