Itachi Uchiha (うちはイタチ, Uchiha Itachi) was a prodigy of Konohagakure's Uchiha clan and also served as an Anbu Captain. He later became an international criminal after murdering his entire clan, sparing only his younger brother, Sasuke.
The Uchiha Clan Downfall. Before assassinating his clan, Itachi sought out the help of Tobi, who he believed to be Madara Uchiha. In a single night, Itachi and Tobi wiped out the entire Uchiha clan, with Itachi taking responsibility of killing his parents.