Having lost three sons to the French and English armies in the World War, Prussian Count Reichendorf laments the days when the Reichendorfs made Prussia "the might of land." Reichendorf, a military general left with only one son, Dietrich, is forced to recruit military men from the prison camp he commands. Axelle, Reichendorf's niece, who became his ward when her parents died, lives in the Reichendorf castle and is courted by the disfigured Captain Elbing. Axelle shows little interest in Elbing, and when he reminds her how he dazzled her before he went into battle, she rejects his affections and tells him that she is engaged to Dietrich. Elbing pleads with her, insisting that his love for her is more intense and enduring than that of any other man, but she is not swayed. Meanwhile, at the German prison camp near the castle, new prisoners are brought in, including the wily and attractive French Sergeant Dumaine. Elbing soon puts Dumaine and the other prisoners to work at the unpleasant task of burial detail. When Dumaine, Fichet and other prisoners escape by overpowering the guards, they break into the Reichendorf castle and take refuge there, but are soon discovered by Axelle and taken back to the prison. One day, after noticing billows of smoke coming from the castle, Dumaine heroically rushes into the castle and puts out a kitchen fire. In gratitude for his valor, Elbing commissions Dumaine, an electrical engineer by profession, to wire the castle. Dumaine's new assignment puts him in close contact with Axelle, and they soon become friends. After one month, Axelle begins to trust Dumaine and suggests that he remove his prison number from his uniform. When news reaches Germany that Dietrich has led his regiment in victorious battle against the French, an end to the war is predicted. Axelle is overjoyed at the news, but Dumaine, whose loyalties still remain with France, is upset. Back at the prison, Dumaine's fellow inmates resent Dumaine's privileged status at the castle, and plan a breakout without him. Soon after Dietrich returns from the battlefront, he discovers his fiancée in the arms of Dumaine, and learns that Elbing, too, is trying to woo Axelle, so he decides to return to the front. When the jealous Elbing learns of Dumaine's affair with Axelle, he sends the Frenchman to be executed despite Axelle's pleas to spare him. Elbing later has a change of heart, however, and decides to call off the execution. News of the Armistice and the end of the war brings with it orders to suspend all disciplinary action against prisoners of war, and Elbing, who sees no further use for himself as a military leader, commits suicide. With the battlelines suddenly erased, Dumaine and Axelle resume their romance with a kiss.