Naruto - Season 4 - Eps 171: Infiltration: The Set-Up!
After Isaribi escapes, Naruto and his team decide to go to the forbidden island and confront Orochimaru and his subordinates. They soon discover that Orochimaru is not the man behind the curtain, but a man known as Amachi. Amachi is the one responsible for turning Isaribi into a monster, so why is she helping him?
About Naruto

Title: Naruto
First Air Date: 2002-10-03
Last Air Date: 2007-02-08
Status: Ended
Rating: 8.4/10 (from 5624 votes)
Language: JA
Seasons: 5
Total Episodes: 220
Network: TV Tokyo
Genres: Animation, Action & Adventure, Sci-Fi & Fantasy
Production Companies: Pierrot, Sound Box, Rakuonsha
Synopsis
Naruto Uzumaki, a mischievous adolescent ninja, struggles as he searches for recognition and dreams of becoming the Hokage, the village's leader and strongest ninja.
Cast

Junko Takeuchi
Naruto Uzumaki (voice)

Noriaki Sugiyama
Sasuke Uchiha (voice)

Chie Nakamura
Sakura Haruno (voice)

Kazuhiko Inoue
Kakashi Hatake (voice)

Hidekatsu Shibata
Hiruzen Sarutobi (3º Hokage) (voice)

Koichi Tochika
Neji Hyuga (voice)

Masashi Ebara
Might Guy (voice)

Yōichi Masukawa
Rock Lee (voice)

Yukari Tamura
Tenten (voice)

Ryoka Yuzuki
Ino Yamanaka (voice)