Shisui Uchiha (うちはシスイ, Uchiha Shisui), renowned as "Shisui of the
Body Flicker" (瞬身のシスイ, Shunshin no Shisui, English TV: Shisui the Teleporter), was ashinobi from Konohagakure's Uchiha clan.
Born into the Uchiha clan, Shisui was noted to be one of the most talented members of the famed clan. He grew up alongside Itachi Uchiha, becoming best friends and forming a brother-like bond. They would regularly train together, having multiple sparring matches. Shisui would also at times help Itachi's younger brother, Sasuketrain. At some point, he fought with Ao who retained an acute memory of Shisui's chakra colour. Later in the anime, Team Shisui was assigned a long mission, which they were tasked with chasing away Kirigakure forces being lead by Ao. The team completed their mission after Ao realised they were facing Shisui and had his team retreat.
When Itachi began to act "oddly", Shisui was instructed by the Konoha Military Police Force to monitor Itachi because the younger Uchiha's position in Anbu was instrumental to the Uchiha's future status in Konoha. Unbeknownst to the clan, Shisui in reality sympathised with Itachi, not wanting the Uchiha to go to war with the village. As the Uchiha continued to grow angrier and more violent from the distrust of the village due to the suspicion of their involvement in the Nine-Tails' Attack on Konoha, Shisui approached Hiruzen Sarutobi revealing the truth to the Third Hokage. Trusting Shisui, seeing as he is Kagami Uchiha's descendant, Hiruzen allowed the Uchiha to spy on his clan for the village. Shisui was perplexed that the clan would not deter from the coup d'état that they were planning and soon became greatly concerned with the consequences that would follow their actions. Ultimately, it was decided that Shisui would use his Kotoamatsukami on Fugaku Uchiha to subtly end the coup d'état plan.
Later, as Shisui prepared to make his move, Danzō Shimura, believing that simply manipulating the Uchiha's leader wouldn't end the conflict and that he would eventually try to manipulate him as well, chose to take Shisui's eyes for himself in the desire to protect the village in his own way. While Shisui effortlessly subdued Danzō at first, the ruthless elder caught Shisui off guard by using the forbidden Izanagi with another Sharingan already in his possession to break free and steal Shisui's right eye. As Danzō and his men surrounded Shisui to take the left eye, Shisui managed to escape.
Fearing that Danzō was right in Shisui's inability to stop the Uchiha's revolt and that the elder would continue to pursue his left eye as well, Shisui entrusted it to Itachi, telling him to protect both the village and the Uchiha name. Shisui wrote a suicide note telling his clan he cannot follow through with the coup d'etat, but his clan's narrow mindednessmade them unable to understand this, believing he would even sacrifice innocent lives for the sake of the Uchiha Clan. The contents of the suicide note also made it appear as though he had crushed his eyes when jumping off a cliff into the Naka River to kill himself in order to prevent conflict from arising over his eyes within the clan. He, at the same time, was able to erase his existence, leaving no corpse behind. In the anime, Shisui was also hoping to use his death to awaken Itachi's Mangekyō Sharingan, succeeding in the goal.