As the U.S. enters the First World War and the draft gets underway, Boynton, Oklahoma, is split by the clash between pro-war, anti-immigrant 'patriots' and anti-conscription socialists. Alafair Tucker is caught in the middle when her brother, a union organizer, pays her a visit. Rob Gunn, fresh off a miners' strike, assures Alafair that he's only come to visit, but she's not so sure. More unsettling, her eldest son enlists, and a group called the 'Knights of Liberty' vandalizes the farm of Alafair's German-born son-in-law. Alafair's younger son, wildly patriotic Charlie, takes a part-time war job. Soon suspicious machine breakdowns delay production, and shift supervisors are murdered. Some blame German spies, others unionists and socialists. But Charlie thinks he knows who the culprit is and devises a way to catch him red-handed. And then there is old Nick-a mysterious guy in a bowler hat who's been hanging around town.