Orochimaru's failed attempt to take Itachi's body (Image via Studio Pierrot) He had no other choice, as Hiruzen had caught him red-handed when experimenting on their fellow Hidden Leaf villagers.

Ultimately, he made a bet with Itachi which he lost. This led to him joining the Akatsuki. Shin Uchiha was one of Orochimaru's test subjects. At some point, he became obsessed with Itachi Uchiha ...