Genre: Adventure

Kabuto fights Team Kakashi and frees Sai. However, Sai, who intends to learn more about his bond with his brother through Naruto's bond with Sasuke, betrays him. Captured, Kabuto gives a vague description of Sasuke's location to the team. Leaving Yamato's wood clone to watch over Kabuto, Team Kakashi enters Orochimaru's hideout and splits up to find Sasuke.

Yamato and the team enter Sai's room and confront him while Kabuto makes his way there as well. Sai tells Team Kakashi that not only was he to help with Konoha's destruction but also act as a spy against Orochimaru. Yamato reveals the secret of "Root"- its members were trained like Kirigakure's students in that they had to kill their friends so as to eliminate their emotions. Sakura returns Sai's book to him, remarking that he still has emotions because he treasures it. Sai then tells the group about his bond with his brother. Finally the team decides what to do about Sai's betrayal outside the lair. In doing so, Naruto tells the group about his own bonds and about how far he's willing to go to bring Sasuke back.

Sai receives a chilling glare from Sasuke's Sharingan that frightens him. Sai gives Orochimaru a bundle with information about Konoha's ANBU. Yamato gives Sakura and Naruto seeds with his chakra that enables him to track them inside the lair, and reveals that he was able to track Sai because he put a seed in Sai's clothing and food during the visit to the hot springs. Kabuto locks Sai in a room, and the boy summons a bingo book from scrolls he carries. Yamato uses a jutsu to open a tunnel into Orochimaru's hideout, and he, Naruto and Sakura travel to Sai's room undetected.

Naruto finally makes sense of the destruction he witnessed around him earlier. Yamato tells Naruto not to rely on the demon because Naruto is strong enough to withstand the demon's terrible chakra. Sai discovers the loss of his book while resting. Team Kakashi browse Sai's book, and they notice that the book (which can be read from both ends) contains different paths of two boys who meet in the middle. Each page has the boys fighting someone new, each time collecting the opponent's armor and weapons into the next page. The pages where the two boys would meet are unfinished. Orochimaru's group reach their base, not realizing that Yamato's wood clone trailed them there. Sai gets a glimpse of Sasuke's silhouette and eyes and discovers that he is the man Naruto and Sakura are looking for.