Watch out! There's a killer on the loose! But fear not, Margaret and Emily, your fearless detectives are on the case, ready to explore 2 stories about serial killers made 100 years apart. Zodiac (2007), based on true events, is Fincher's classic thriller, lightly inspired by M (1931), which basically invented the procedural drama. Lock your doors, wrap up and take this spooky journey with us.