Harold Whitley, a member of New York's idle rich, is upset when the United States enters World War I. Upon learning that married men are exempt from the Selective Draft, Harold urges his fiancée Mary to wed him quickly, but Mary indignantly threatens to break their engagement. At the twenty-story skyscraper that Harold's father is building, Mary meets Jim Kelly, the contractor's son, and is impressed as he rises on a beam. Jim returns Mary's gloves to her Fifth Avenue address, where Harold insults him. At training camp, Jim, enthusiastic about the draft, is promoted to aviation captain, while Harold, who exhibits cowardice as a captain, is released. In France, Jim is knocked unconscious by a shell and nursed by Mary, now in the Red Cross. Jim captures a German raiding party, and after he makes them exchange clothes with allied soldiers, they are shot by their own men. When Mary is abducted by a German prince, Jim pursues on horseback, tumbles over a cliff, swims ashore and arrives in time to rescue her. They then escape in an airplane.