Search for Tsunade

Episodes 86—100, Chapters 149—171: This arc covers Naruto's and Jiraiya's search for Tsunade, so they can persuade her to become the Fifth Hokage as well as healing Kakashi Hatake and Sasuke Uchiha from the effects of the Mangekyo Sharingan which was the result from their battles against Sasuke's brother Itachi (and for Might Guy to have her heal Rock Lee from the injuries he received from his battle against Gaara). In the meantime, Orochimaru and Kabuto also search for her, aiming to convince her to heal Orochimaru's arms. This arc also includes Naruto's introduction to and learning of his signature move - the Rasengan.