|This is the article on the story arc. If you are looking for the article on the actual invasion, head to Invasion of Konoha.|
The Invasion of Konoha Arc was included in Part I of the series, and comprised chapters 115 to 138 of the manga and episodes 68 to 80 of the Naruto anime. The previous arc directly led into this one. This arc covered Gaara's change of heart towards people after battling Naruto, 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 vs. Gaara
Initially, Sasuke was sent after Gaara by Genma. Sakura, Shikamaru and Naruto followed Temari and Kankurō, who had been charged with protecting Gaara while he recovered from his battle with Sasuke. It was later revealed that Shino also chased after them, claiming that even though the exams had been disrupted, he still wanted to have his battle with Kankurō. Shikamaru fell behind to stop nine Sound Village jōnin from following them, although he was low on chakra from his own match. His Sensei, Asuma, arrived just in time to save his life.
In the anime, Temari set traps in order to deter Sasuke before engaging him in combat herself.
Kankurō stopped to fight Sasuke, giving Gaara enough time to recover. Shino, however, declared that Kankurō was his opponent. 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. Shino was rendered unconscious after being poisoned earlier in the fight, until his father came to his aid to counteract the poison. Finally, Sasuke caught up with and fought Gaara. Gaara began to transform into his Shukaku state, overpowering Sasuke with ease.
Naruto and Sakura arrived just as Sasuke was about to be killed. Gaara continued to attack Sasuke until Sakura placed her own body between them. Furious, Gaara pinned her to a tree with one of his sand claws, and proceeded to taunt Naruto. He stated that unless he was defeated, Sakura would soon be crushed by the force of the sand binding her to the trunk.
Naruto was clearly outmatched at first, but as the battle continued, he gained the upper had by employing a clever series of tactics taught to him by both Kakashi Hatake and Jiraiya. He used One Thousand Years of Death to injure the partly transformed Gaara, preventing him from moving while Naruto attacked him with clones. Enraged that he had succumbed to Naruto's assault, Gaara took on his full Jinchuriki form and attempted to finish Naruto off with his Sand Binding Coffin and Sand Waterfall Funeral techniques. Naruto managed to free himself from Gaara's jutsu by summoning Gamabunta, who, after a little convincing from his son, Gamakichi, decided to fight Shukaku.
Gaara then used his Feigning Sleep Technique to call out Shukaku's true consciousness. Gamabunta, unable to match Shukaku's might, told Naruto that he would have to wake Gaara up in order to dispel the jutsu. Using a Combination Transformation technique, Naruto transformed Gamabunta into a giant fox (the Nine-Tails itself in the anime). In that form, Gamabunta was able to dig his claws into Shukaku long enough for Naruto to punch Gaara awake. Angered, Gaara once more attempted to trap Naruto with his Sand Bunding Coffin. Gamabunta tried to help by concealing Naruto with his tongue, but Gaara was able to get to him from below. In the end, Naruto escaped by using the Nine-Tails' chakra. Free, he launched himself at Gaara once more, and unable to strike him with his fist, opted to head-butt him instead. Both injured, blood trickling down their foreheads, Gaara's sand crumbled away around them.
With that, Gaara and Naruto only had enough chakra for one last attack. They leaped at each other; Naruto's will won and Gaara was knocked to the ground. Unable to walk, Naruto began to crawl to Gaara's side. At that moment, Gaara realized that they were very similar; they both were the containers of monsters, both had been ostracized by the people of their village, and had led unhappy, lonely lives as a result. Gaara wondered what made him so strong, and Naruto explained that although he was able to empathize with Gaara, he would never let him hurt the people who had saved him from the hell of loneliness. As Naruto continued to crawl, a recovered Sasuke dropped down beside him, informing him that Sakura was free from Gaara's sand. Temari and Kankurō landed near Gaara; although they were prepared to fight Sasuke again, Gaara shocked everyone by saying that it was over. In agreement, Gaara's siblings carried him away. Naruto watched them go, and then with a smile on his face, fell asleep.
In the end, what enabled Naruto to triumph was his undying devotion to those closest to him. His loyalty was much more powerful than Gaara's hatred ever could have been. After the battle, Gaara apologized to his brother and sister, wondering whether he could be important to people someday.
Also, as Gaara had been an opponent that Sasuke could not face equally, Naruto's role in his rivalry against Sasuke was altered. His victory induced deep feelings of inferiority in Sasuke, despite the façade he continued to maintain. Later, a funeral was held in memory of the Third Hokage.
The invasion was called off, as Orochimaru was unable to use any more techniques, and the Suna and Oto shinobi retreated. The surviving Suna ninja also discovered the body of their leader, the Fourth Kazekage, and realised that Orochimaru had murdered him and disguised himself as the Kazekage, thereby playing both sides of the alliance he had created, which resulted in their reestablishing their alliance with Konoha.