Yakushiji Ryōko no Kaiki Jikenbo (Japanese: 薬師寺涼子の怪奇事件簿, lit. "Ryōko Yakushiji's Strange Case Files"), known in English as Ryoko's Case File, is a Japanese light novel written by Yoshiki Tanaka and illustrated by Narumi Kakinouchi. It was adapted into manga and an anime television series, two Drama CDs had also been released prior to the anime adaptation with different voice actors.