 When he and Kakashi rescue Rin when she is kidnapped by Hidden Stone Ninja during a mission, Obito's right side is crushed in a landslide.Obito, thinking that he was going to die, had Rin transplant his left Sharingan into Kakashi to replace Kakashi's original left eye.Late in Part II of the manga, it is revealed that Obito was saved by an elder named Madara Uchiha and outfitted with prosthetics.