Fired up by the story of Joan of Arc, eight-year-old Mary ("Baby"Marie Osborne) decides to "do her bit" when America enters WWI. Before long, Mary has organized her schoolmates into an auxiliary army. The kids prove that they aren't "summer soldiers" when they rush to the rescue of an old inventor (Herbert Standing) whose aerial torpedo is stolen by a German spy. Setting a precedent for such future children's entertainments as Emil and the Detectives the kids converge upon the "Hun" and save the day. But the story isn't over yet: the inventor turns out to be Mary's grandfather, and by fadeout time the diminutive heroine has orchestrated a reconciliation between the old man and her mother (Marian Warner). ~ Hal Erickson, Rovi