Before diplomatic relations between the United States and Germany have been severed during World War I, Count Johann von Bernstorff establishes an intricate spy network in America, headed by the treacherous Otto Goltz and his ally, Wolff von Eidel. Their activities result in labor strikes, factory explosions, and transportation disasters. Headquartered in a major U.S. industrial center, Otto marries Lillian O'Grady and treats her so brutally that she eventually dies. Lillian's death is avenged by a young American soldier named Dick Gregory, who is in love with her sister Rosie. Following Otto's death, von Eidel is arrested, but when a group of German sympathizers tries to rescue him, a patriotic vigilante group attacks the jail, shooting the spy and imprisoning the disloyal Americans. In the end, as American forces storm France, Kaiser Wilhelm grows desperate.