The Powerful Helper

is episode 200 of the original Naruto anime.

Synopsis
The group sets out to disarm the traps without Genno finding out. The research then concludes that Genno set the traps 30 years ago, as part of a mission for the Hidden Dragonfly Village, which was destroyed by another village shortly after he completed his mission, resulting in his son's death. Naruto comes to terms with the fact that the old man he befriended attempted to destroy the village, and finds a lead that Genno is in the mountains behind the village.