An American doughboy, stationed in France during the Great War, goes on a daring mission behind enemy lines and becomes a hero.

As a reporter, Dick Farrington is sent to cover an assignment that promises a big story. A lawyer has advertised for an ex-Marine who is a boxer. He makes good beating up a gang of roughnecks picked for the purpose, and secures the mysterious job that is filled with danger. It is to guard the heiress Lady Chatfield, but the hero is told nothing as to the secret in back of it all. Dick poses as Lord Grantmore, wears a monocle, and otherwise acts like a titled Englishman. They proceed to the mining town of Goldbrook, where the heiress is to occupy a mysterious mansion on the occupancy of which hinges a great fortune. The engineer of the mines is deeply interested in thwarting the plans of Lady Chatfield, and with his gang of roughneck miners makes things lively for the pugilist star in a series of fights that are hair raisers.