Adapted from the novel by author Kei Oishi, Ataru Oikawa's Apartment 1303 explores the horrific case of a purportedly haunted apartment. Sayaka was excited at the prospect of striking out on her own; so excited that she invited her closest friends to her new apartment to celebrate. In the middle of the party, however, Sayaka begins acting very strangely and lunges over the balcony to her death. But Sayaka was never suicidal, and her friends refuse to believe that she could have taken her own life. When Sayaka's sister Mariko decides to investigate, she discovers that her sibling wasn't the first to take a fatal plunge from that particular apartment. Though Mariko is by no means superstitious, she's about to come into contact with a force more evil and powerful than she could ever imagine.