Overview: A cold-blooded killer begins his reign of terror in 1969. A panicked San Francisco lies in the grip of fear. Nobody knows where - or when - he will strike next. In his taunts to local police and newspapers, the killer claims to have murdered as many as 37 people. A chilling mystery is about to unfold. How did visionary director David Fincher turn this story into what critics call the gold standard for fact-based serial killing thrillers?