Invasion of Konoha Arc

The Invasion of Konoha Arc was included in Part I of the series, and comprised episodes 68-80 of the Naruto anime, which is parallel to chapters 50-57 of The Life of a Kunoichi Shinobi. The previous arc directly led into this one. This arc covered Gaara's change of heart towards people after battling Naruto, and him seeing Kristin's bonds with her friends, as well as the resonance between her and Helena, and the death of the Third Hokage at Orochimaru's hands. This arc is preceded by the Chūnin Exam Arc and is followed by the Search for Tsunade Arc.

The Third Hokage vs Orochimaru
Three giant snakes were summoned, and broke down the walls guarding Konoha before proceeding to wreak havoc on the village. Meanwhile, approximately one-hundred and twenty Suna and Oto ninja invaded the village. Suna had joined the attack because their daimyō had mistreated their village and had showed favour towards Konoha; this attack was to show that Sunagakure didn't appreciate being treated as second-rate in their own country.

Meanwhile, Orochimaru began to fight the Third Hokage. Orochimaru revealed his secret: he had created a ninjutsu to grant him immortality. Orochimaru's spirit was able to live forever, but he must change bodies frequently. Orochimaru had also mastered Summoning: Impure World Reincarnation, which allowed him to summon the souls of the first two Hokage at the cost of sacrificing the two remaining genin of Team Dosu. It appeared that the Third managed to stop the third coffin, containing the Fourth Hokage, from being summoned. Sarutobi then used the Summoning Technique to summon Monkey King: Enma.

The summoned Hokage, although perfect in form to the original and retaining all their abilities, had lost their personalities, and were merely Orochimaru's slaves. They couldn't be killed, since their bodies simply regenerated. The Third realised that he must do something about their souls, and used Dead Demon Consuming Seal, the same technique the Fourth Hokage had used to seal the Nine-Tails. Sarutobi was able to sacrifice two Shadow Clones to seal away the souls of the two Hokage, and then attempted to do the same to Orochimaru. However, Sarutobi was low on chakra and stamina, and thus was reduced to doing the next best thing: sealing away Orochimaru's arms, so that Orochimaru would be unable to perform any more techniques. The Third died with a smile on his face.

Naruto & Helena vs Gaara
Initially, Sasuke was sent after Gaara by Genma. Sakura, Kristin, Shikamaru, Choji, and Naruto chased after Temari and Kankurō, who had been charged with protecting Gaara until he had recovered from his fight with Sasuke. It was later revealed that Shino also followed them, claiming that he wanted to have his battle with Kankurō. Shikamaru fell behind to stop nine Oto jōnin from following them, although Shikamaru was still low on chakra from his own match. However, Asuma arrived to bail him out. After resting a while Shikamaru, along with the ninja hound Angel, set of after the others in hopes of reaching Kristin before she unleashed Helena's full powers.

Kankurō stopped to fight Sasuke, giving Gaara enough time to recover. However, Shino declared that Kankurō was his opponent, as they had been set to fight during the Chūnin Exams. Shino was able to defeat Kankurō by placing a female insect on him. The scent of this insect attracted all of Shino's other insects, which then overpowered Kankurō, but Shino was also rendered unconscious after being poisoned earlier in the fight, until his father came to his aid to remove the poison. Finally, Sasuke caught up with and fought Gaara. Gaara began to transform into his Shukaku state, overpowering and defeating Sasuke.

When Sasuke was about to be killed, Naruto, Krstin, Sakura, and Choji arrived. Gaara continued attempting to kill Sasuke until Kristin and Sakura placed themselves between them. Gaara trapped bot girls in one of his Shukaku sand claws and pinned them to a tree, using a kunai knife hidden in his claw to stab Kristin's chest. He then taunted Naruto, stating that, unless he defeated him, Sakura would eventually be crushed by the sand claw trapping her to the tree. Kristin, on the other hand, willingly gave Helena control over her body so she could heal from the near-fatal wound. To signify Helena taking control, Kristin's hair color changed from its duel-colored state to solid, dark purple.