The Little Patriot (1917)

Instilled with the spirit of patriotism after her teacher reads to her the story of Joan of Arc, Marie Yarbell goes home, persuades her father to enlist and then organizes a "military company" comprised of her playmates. Wealthy old Nathan Mulhouser, who is financing the development of a torpedo, is so touched by the children's patriotism that he buys them a flag. Marie's mother rents out a vacant room to Hertz, a stranger, who instructs her to see that no one enters his room because he is working on an important invention for the government. Curious, Marie follows Hertz as he leaves the house carrying a suitcase. He goes to a building that houses Mulhouser's laboratory, tosses in a bomb and runs away. Marie disposes of the bomb in time, but is stunned by the explosion. Mulhouser finds Marie in a state of shock and takes her to his home. Meanwhile, Mr. Yarbell has returned home at his wife's alarm and finds Marie's soldiers holding the spies prisoner. Mulhouser finally ascertains Marie's identity, discovering that she is his granddaughter, and all ends happily.