Sadako was born in 1947 to Shizuko Yamamura and Dr. Heihachiro Ikuma in Oshima Island. The year before, Shizuko gained psychic powers after retrieving an ancient statuette of En no Ozuno from the ocean. Shizuko also gave birth to a baby boy but he died four months later due to an illness. Planning to move to Tokyo with Ikuma, she entrusted her mother to take care of baby Sadako. At Ikuma's encouragement, Shizuko displayed her psychic powers during a publicized demonstration. However, Shizuko bowed out of the demonstration due to migraines brought on by her powers. The press denounced Shizuko as a fraud because of this. Depressed, Shizuko eventually returned to Oshima Island and committed suicide by jumping into Mount Mihara. Meanwhile, Ikuma attempted to unlock psychic powers of his own by meditating beneath a waterfall, which ended up causing him to contract tuberculosis, requiring him to recuperate in a sanatorium in the Izu Peninsula, leaving Sadako to be raised by Shizuko's relatives. Like her mother, Sadako was a powerful psychic; however, whereas Shizuko could only burn images onto paper, Sadako could also project images into electronic media, such as TV.