Sasori's Real Face

is episode 21 of the Naruto: Shippūden anime.

Synopsis
With his puppet destroyed, Sasori reveals himself to Chiyo and Sakura, looking no older than when he left his village over twenty years ago. Meanwhile, Temari's team, along with Kankuro and Ebizo, continue to make their way towards the Land of Rivers, where Ebizo tells the others of the strongest ninja in Sunagakure's history, the Third Kazekage, and his mysterious disappearance. Back in the Akatsuki lair, Sasori summons the Third Kazekage puppet, whom he had kidnapped and turned into a Human Puppet many years ago. Using its weapons, which are even more dangerous than Hiruko's, Sasori is able to catch Sakura in a cloud of poison gas.