It's summer vacation! Rantaro and his goofy friends at the Ninja Academy must retrieve a stolen magic sword against great odds so that they won't have to do extra schoolwork! The live action feature film version of the popular manga that's been going for 27 years and sold 8.7 mil. copies.At a time when nations are warring, a sword with mysterious power called "Heaven's Sword" is stolen. The sword is said to give... its wielder the power to conquer the world. Various ninja all over Dokutake Castle and beyond also manuevering for this sword of immense power. Rantaro and his classmates are assigned to retrieve the stolen sword, their first real ninja mission.