Cash Laramie, The Outlaw Marshal, faces his wildest adventure yet when the Sundown Express, billed as the fastest train in the west, is seized by a ruthless gang. The desperadoes run the train back and forth on the same stretch of open ground, eliminating any chance for lawmen to board and retake the locomotive. They deliver their demands with a corpse: Give us $100,000 before dusk or we will kill more passengers every hour until the ransom is met.

Cash has faced miscreants before and knows he can beat these guys, but how can he get on the Express hurtling down the tracks at seventy miles per hour?

Aboard the train, things are grim. Famed actress Lillie Langtry and the other captives sit frightened, wondering if they’ll be next. But not disguised railroad detective Calvin Carter. He reckons the train’s speed thwarts any chance for a boarding party to save the day, so the former actor makes sure he’s in the marauders’ spotlight, even if it means his final curtain call.

With a rescue plan that feels like a suicide mission, Cash and fellow marshal Gideon Miles must board the speeding train and take down the gang before any more innocent lives are lost.