The movie is based on Kazuhisa Sakaguchi`s 2013 novel Nintama Rantaro: The Dokutake Ninja Team`s Strongest Strategist and illustrated by Soubee Amako. The story centers on Rantaro’s teacher, Hansuke Doi, losing a battle against Sonnamon, and Zatto Konnamon becoming a teacher at Ninjutsu Academy. After heading off to a duel with the Tasogaredoki ninja, Moroizumi Sonnamon, Mr. Doi goes missing. While Yamada and the sixth graders begin searching for him, the Tasogaredoki ninja squad leader, Zado Konnamon, and Sonnamon take the podium in the absence of their homeroom teacher in Class 1.
Meanwhile, Kirimaru accidentally learns about the situation Mr. Doi is in. As the sixth graders continue their search, Amagi, the cold-hearted strategist of the Dokutake Ninja Squad, suddenly appears in front of them. His face is the spitting image of Mr. Doi. Facing the strongest enemy yet, the ninjas powerful bonds will be put to the test. Will Rantaro, Kirimaru, Shinbei, and the others be able to bring Doi-sensei back?
