Danzō Shimura

is more militant than most in the Leaf Village, favoring aggression and war over passiveness and peace. In the past, he competed with Sarutobi for the position of Third Hokage. He created the (now disbanded) ANBU training department known as and acted as its head. Danzo was the one who recommended that Sai be placed in Team Kakashi. He appears to have lost an arm at some point, the cause of which remains unknown, and may have also lost his right eye.
 * Seiyu: Hiroshi Ito

Despite Danzo's apparent support for the Hokage and Konoha, Tsunade does not trust him; this is apparently well founded, as Danzo had given Sai a secret mission that Tsunade was unaware of: sending Sai to contact Orochimaru and offer to act as a subordinate for him. Yamato believes that Danzo is trying to take over Konoha with Orochimaru's help. This is apparently proven when it is revealed that the envelope Danzo sent Orochimaru was full of pictures and information on the true identities of Konoha's ANBU. However, all of these are nothing more than a front to let Sai get close to Orochimaru, so that Sai can execute his true mission: the assassination of Sasuke Uchiha. After learning of the failed assassination attempt of Sasuke, and Sai's attachment to Team Kakashi, he merely states that "emotion brings hatred, and hatred brings war."

He is also mentioned by Tobi to be one of the three surviving that know "the truth" of Itachi Uchiha.