Kakashi Enlightened!

Sakura and Chiyo track Naruto and Kakashi, but the poison in Chiyo's body drags on her progress and nearly makes her collapse. Sakura recognises that only raw willpower keeps the elder conscious and urges her to return to Sunagakure for treatment, yet Chiyo insists she still has a task to finish. Supporting her, Sakura presses on, recalling Naruto's fury when Deidara sat atop Gaara's body and pronounced the Kazekage dead.

Chasing Deidara as he flies overhead on his clay bird, Kakashi tries out Kamui, his Mangekyō Sharingan's dimensional warping technique, to drag his foe into a vortex. The strain proves immense, and though he cannot kill Deidara, he warps away the man's right arm. With both arms now gone, Deidara flees, and Kakashi, exhausted, is forced to rest. Believing himself safe, Deidara drops his guard, and Naruto strikes with a Rasengan that splits the clay bird apart. Naruto pries Gaara's body from the wreckage and pleads with him to wake, only to realise in anguish that Gaara is truly dead.

This is episode 29 of Naruto Shippūden, part of the Kazekage Rescue Mission arc, adapting chapters 276 and 277. Team Guy sets out to reinforce Team Kakashi, and Neji's Byakugan confirms both the rescue and Gaara's death. Vowing to avenge his friend, Naruto draws on the Nine-Tails' chakra, hammering Deidara into the ground with the help of shadow clones and pummeling him bloody. When his Rasengan is dodged by a substitution, Naruto's hatred deepens and the fox's red chakra envelops him, sprouting a single tail and transforming him into his One-Tailed form. The episode uses the opening theme Hero's Come Back!! and the ending theme The Way ~ to you all.