Kakashi Chronicles ~ Boys' Life on the Battlefield ~ Part 2

Making his way toward Kannabi Bridge, Kakashi winces from his wound and mulls over Obito's refusal to abandon Rin. Obito, meanwhile, tracks the two Iwa ninja to a cave, but the slap he gives himself to focus betrays his presence. Taiseki moves to handle Obito while Kakkō presses Rin with an interrogation genjutsu. Using camouflage, Taiseki nearly kills Obito, only for Kakashi to arrive and slash at him with the White Light Chakra Sabre. When Taiseki attacks again, Kakashi shields Obito and loses his left eye to the blade. In that moment Obito finally awakens his Sharingan and stabs Taiseki down, then Kakashi bandages his eye and the two enter the cave to free Rin.

Guided by his new Sharingan, Obito helps defeat Kakkō, but the enemy triggers a cave-in as they reach Rin. A falling rock strikes Kakashi, and Obito hurls him clear before a massive boulder crushes the entire left side of his own body. As Kakashi weeps over the pinned Obito, the dying boy asks Rin to transplant his left Sharingan into Kakashi's empty socket. With the eye implanted, Kakashi cuts down Kakkō using the sabre and Chidori. The remaining Iwa ninja then collapse the cave completely, burying Obito, who in his final thoughts mourns dying just as he and Kakashi had begun to get along.

This is episode 120 of Naruto Shippūden, part of the Kakashi Gaiden arc, adapting chapters 242, 243, and 244, and it aired alongside Part 1 as episode 119. Outside, Kakashi holds off the surrounding enemies to let Rin flee, honoring his promise to protect her, until Minato arrives with the Flying Thunder God Technique and defeats them all. Following the bridge's destruction, the Third Hokage proclaimed that two heroes were born that day, each bearing a Sharingan, and Kakashi earned the title Kakashi of the Sharingan while Obito received a memorial as a fallen shinobi. The episode uses the opening theme Light of a Firefly and the ending theme My Answer.