Two days before her fourteenth birthday, Ashley Mizuki Robbins receives a package from her father, Richard Robbins, whom she thought was dead. The package contained a small handheld device called a Dual Another System, or "DAS" (Dual Trace System, DTS in the American release), along with an invitation to meet him on Blood Edward Island. The following day, her and her aunt , Jessica Robbins, set off for the island. While there, Ashley meets "D", a ghost with no memories, who has been wandering the island alone for decades since his death. Ashley attempts to aide D in uncovering his lost memories, while also uncovering the truth about her father, the murder of her murder, and the mysterious project, code named "Another".