Between 1968 and 1983, a San Francisco cartoonist becomes an amateur detective obsessed with tracking down the Zodiac Killer, an unidentified individual who terrorizes Northern California with a killing spree.
Five interwoven stories that occur on Halloween: an everyday high school principal has a secret life as a serial killer; a college virgin might have just met the guy for her; a group of teenagers pull a mean prank; a woman who loathes the night has to contend with her holiday-obsessed husband; and a mean old man meets his match with a demonic, supernatural trick-or-treater.