Hearts of the World (1918) is a silent film directed by D.W. Griffith, a wartime propaganda classic that was filmed on location in Britain and near the Western Front, made at the request of the British Government to change the neutral mindset of the American publicTwo families live next to one another in a French village on the eve of World War I. The Boy in one of the families falls for the only daughter in the other family. As they make preparations for marriage, World War I breaks out, and, although the Boy is American, he feels he should fight for the country in which he lives.

When the French retreat, the village is shelled. The Boy's father and the Girl's mother and grandmother are killed. The Girl, deranged, wanders aimlessly through the battlefield and comes upon the Boy badly wounded and unconscious. She finds her way back to the village where she is nursed back to health by The Little Disturber who had previously been a rival for the Boy's affections. The Boy is carried off by the Red Cross.

Upon his recovery, the Boy, disguised as a German officer, infiltrates the enemy occupied village, finds the Girl, and the two of them must kill a German sergeant who has discovered them. Von Strohm, by whom the Girl had narrowly escaped rape earlier in the story, discovers the dead sergeant and locates the Boy and Girl who are locked in an upper room at the inn. It's a race against time with the Germans trying to break the door down as the French return to retake the village.