Based on a long-running gag manga by Sobee Amako and a subsequent TV anime series, the film is set in the Sengoku period and revolves around an 8-year-old boy named Rantaro who attends a school for young ninjas. While there, he befriends Shibe (Fuuta Kimura), the son of wealthy merchant, and Kirimaru, an orphan boy who lost his parents during a war.
Superb trailer.