It’s the summer of 1990, and crime in New York City is at an all-time high. Daily headlines bring fresh stories of random violence and stranger-on-stranger crime. Then, one day in June, someone calling himself “Zodiac” writes a disturbing letter to the New York Post. He claims to have killed three people in Brooklyn according to their astrological signs, and he promises to kill nine more. When the shootings check out, the NYPD forms a Zodiac Task Force. Retired Lieutenant Michael Ciravolo and retired New York Post reporter Anne Murray recount their involvement in the early days of the investigation.