Our story opens in the office of the Mexican junta in a Texas town, not many miles from the border, presided over by M. Oliverez, supposedly the agent for the Mexican-American Fruit Co. Pedro, a young Mexican attached to the Junta, is in love with Blance, the agent's daughter. Arrangements have been made to run a quantity of fire arms and ammunition across the line to the Mexican insurgents. In loading a freight care with the contraband every patriot thereabouts takes off his coat and works with a will, all except Monte. Oliverez coming on the scene and finding everyone working but Monte, upbraids the lazy fellow and threatens to strike him. This arouses the revengeful spirit of Monte; he sneaks away and advises the American authorities that the Mexican filibusterers are attempting to rush fire arms across the border. Although compelled to act on the information furnished by him the Secret Service man are disgusted with the traitor and look upon him with contempt. In the meantime Blanca, who suspected Monte's contemplated treachery, watches and sees him as he enters the office of the United States Secret Service. Quickly returning to the place where the ammunition is being loaded, she warns the Mexicans and the train is ordered to pull out immediately. The Secret Service men arrive on the scene just as the train is leaving the station. Blanca's daring feat of uncoupling the car containing the ammunition and the transport of the contraband across the border make a thrilling ending.