Nintama Rantarō: Invincible Master of the Dokutake Ninja

Doi, a mentor to the young ninja apprentices known as 'Nintama' at the Ninjutsu Academy, departs for a duel against a warrior from a rival clan and vanishes without a trace. His students are gripped by worry for their teacher's fate. Simultaneously, troubling news reaches the Academy: their rivals at Dokutake Castle are scheming a dangerous plot that threatens the entire institution. The little ninjas must now leverage every skill learned in class, their quick wits, and unwavering friendship to find their missing mentor and unravel the enemies' cunning plan.