Graysmith worked as a political Cartoonist for the San Francisco Chronicle in 1969 when the Zodiac Killer case came to prominence. He attempted to decode letters written by the killer and became obsessed with the case over the next thirteen years. His marriage to his second wife Melanie ended in divorce, which he directly attributes to his intense interest in the case. Graysmith wrote two books about the case, eventually giving up his career as a Cartoonist to write five more books on high-profile crimes, one of which became the basis for the film Auto Focus (2002). The critically acclaimed movie Zodiac (2007), directed by David Fincher, was based on his books and featured Jake Gyllenhaal as Graysmith. Graysmith now lives in San Francisco.