MPD-Psycho opens Kobayashi Yôsuke on trial for murder. The accused, a male in his late 20s, claims his name is Kazuhiko Amamiya, not Yôsuke. After sentencing, the accused suffers a series of delusions where he sees a lamppost and a murdered woman. He sees himself holding a blood-stained knife and hears someone calling his name. The following scene reveals the trial as a nightmare, and Yôsuke discussing the dream with his girlfriend.
Yôsuke, a police detective, is called to the scene of a murder, where he finds an eerie similarity to the murder in his nightmare. As he investigates what become a series of murders, each with a tell-tale 'barcode' tattoo on their eyeball, he tries to come to terms with his condition, which has yet to decide if it will be a gift, or a curse.