GAMER

A serial killer wants to be the best. He turns a yellow cab into a killing machine and writes a letter to the leading sports writer in NYC telling him he is going to kill one person a week. This will send the City into a panic. He picks, as his victims prominent New Yorkers, his former classmates from prep school and some random elderly people.
Ian MacDonald, a seasoned Assistant District Attorney in the New York County (Manhattan) District Attorneys Office works with the NYPD to try and stop the killings.