A ninja kid and his little brother show up in a normal Japanese town and turn every single day into a ridiculous problem-solving game where the answer is always funnier than the setup. There's no stakes, no arc that matters, just Hattori figuring out how to help someone using ninja logic that makes zero sense until it does. 694 episodes and it never runs out of new ways to make a simple situation explode into chaos, which is exactly why people still talk about it forty years later.

Hattori, a young ninja from the Iga mountains, moves in with the ordinary Sanyo family so he can go to a regular school. He becomes friends with Kenichi Sanyo, who is his age, and attends classes in secret. His brother Shinzo, the ninja dog Shishimaru and Kenichi's girlfriend Yumeko sometimes join him. Trouble comes from Kemumaki, a Koga ninja who opposes them, and his wicked partner Kagechiyo the Shadow-cat. Adapted from Fujiko Fujio A's manga, this short-episode comedy shows Hattori and his brother working to become great ninjas while landing in one funny situation after another.