Joan, an earnest little orphan who lives in an asylum near the World War I training camp at Plattsburg, reads the story of "Joan of Arc" and soon imagines that she is the reincarnation of the peasant-soldier. As she sits in the cellar reading, she hears voices plotting against the government. She thinks the voices are from another world but they actually belong to a group of German spies. The agents plan to acquire the important invention of a young man named Ingleton, who is staying at the camp...