NARUTO: Shippuuden - Kizuna

A mysterious group of ninjas makes a surprise attack on the Konohagakure, which takes great damage. The nightmare of another Shinobi World War could become a reality. Sasuke, who left Konoha to kill his brother, Itachi, appears for the second time in front of Naruto at an unknown location to prevent it from coming to fruition.

(Source: Wikipedia)