Drive Towards Darkness (闇への疾走, Yami e no Shissō) is episode 196 of the Naruto: Shippūden anime.
While on the way to Konoha, Taka briefly stops by a construction Sasuke recognises. He thinks back to when he first came across it. During a training section near the location, Sasuke remembers how he was falling behind Naruto after he defeated Gaara. He punches a tree and uses Chidori to take some of them out. A girl named Naho almost falls from a cliff nearby and Sasuke saves her. Later, Sasuke and Kakashi had been sent to investigate national wanted list criminals, and Naruto, Sakura and have been sent to escort Naho, a relative of the Fire Daimyō, to Shizume village. Naho wants Sasuke to escort her, but he was with Kakashi in another mission. Naruto disguises himself as Sasuke so Naho agrees to go with them. After Sasuke and Kakashi noted that the fortress was empty, Naho's group was intercepted by Sadai and his associates. Naruto, Sakura, and Naho come across the criminal and his associates. Naruto defeats the associates, but can't take down their leader. They're all captured. Kakashi uses his ninken to track the criminal. Sasuke appears and the leader mocks him, mentioning he alone in his clan wasn't worth killing, mirroring Itachi's words. Sasuke takes on the leader, who reveals an Earth Release Armour, the reason he's able to take on so many attacks. Sasuke defeats him with Chidori, and proceeds to keep punching him. Kakashi stops him and Sasuke goes back to Konoha by himself. Naho comments that Sasuke is scary, but Naruto assures her that Sasuke just has a lot going on with him at the moment, and promises to take her to see him once he's better.
When Sasuke uses his Sharingan, it has three tomoe instead of two. Sasuke's Sharingan later gained three tomoe, during his fight against Naruto at the Valley of the End.