In New York, a girl was killed after boarding a car. Megan (Alicia Dushku Eliza Dushku), a policewoman, investigated the case. She was keenly aware that the girl's last name was the same as her first name and the initials of the crime, but there was no clue. Megan tried every means to investigate the case, but found nothing. On the contrary, Megan's mental pressure accumulated day by day. She began to see the phantom of the murdered girl. Finally, he ran out of energy and even chose to commit suicide, and finally had to receive psychiatric treatment. Two years later, when there was another murder of a girl who conformed to the rules of the acronym, Megan took part in the investigation again despite the opposition of her boss. While she and her partner were investigating multiple suspects, the "first letter killer" targeting girls became more and more frequent. Can Megan collage the truth about the killer? This film is adapted from a real case.