Six-Tails Unleashed

The Six-Tailed Beast arc is from Part II starting at episode 144 of the anime.

Summary
The Six Tails arc features Utakata, the jinchuriki of the Six-Tailed Slug. It starts out when Hotaru and her guardian, Tonbee are being attacked at their mountaintop fort. Utakata and Hotaru escape with En no Gyōja's secret kinjutsu, while Tonbee tries to hold off the attackers. Tonbee is easily defeated, and the attackers consisting of Akaboshi, Nangō, Chushin, and Benten go after them. Naruto and the new Team 7 are assigned by Tsunade to go and protect Hotaru on her way to the Tsuchigumo clan's secret village. When Naruto, Sakura, Sai, and Yamato find the fort, they discover Tonbee, who has been viciously attacked by the four-man bandits. Sakura stays and heals Tonbee, while Naruto, Sai, and Yamato follow Utakata and Hotaru. Naruto catches up to Utakata and Hotaru, and Utakata attacks Naruto with some of his Soap Bubble Ninjutsu. After Utakata learns that they are not attackers, he entrusts the protection of Hotaru to them. In the next episode, we see some scenes of Utakata's past, including a vision of his master attempting to draw out his tailed beast. Hotaru refuses to let the leaf ninja escort her to the Tsuchigumo clan's secret village. Sai then tricks her into thinking that giant leeches are falling on her and she begs Naruto for protection. When they reach the hidden village, Naruto leaves the village with a suspicious feeling because of the way that the villagers looked at Hotaru. Utakata also starts fighting the four-man bandit group, and starts to gain the upper hand easily, but then they trap him in a Lightning Release barrier that implodes.

On the third episode of the series, we see Hotaru's uncle betraying her to the four-man bandit group, but when they think that they have found the hidden scroll, it turns out to be a bomb. Hotaru escapes, and she meets up with Utakata in the forest. He faces off against the bandits again, and quickly flees. When they are alone, Hotaru shows Utakata some inscriptions on her back. Kirigakure Hunter-nin then track down Utakata, and incapacitate him.Utakata is then struck by the water whip jutsu and lightning release: electromagnetic murder

Episodes