The central Knott's Scary Farm backstory focuses on the witchcraft trial of Sarah Marshall, her transformation into the Green Witch during her execution at the hands of the Hangman and the events that unfolded in Calico Ghost Town during the decades that followed.

Knott’s Scary Farm is the world's first and longest-running theme park Halloween event, originating in 1973 at Knott's Berry Farm in Buena Park, California. The backstory began as a simple "Halloween Haunt" created by park employees who wanted to drive attendance during the slow October season. The initial event was just a few nights of spooky decorations and a handful of "monsters" (many of whom were local theater students) wandering the Ghost Town area. The event's success was largely due to the creativity of Larry Vincent (known as the horror host "Sinister Seymour") and the legendary "Monster Tom" (Tom Scherman), who helped design the first walk-through mazes. Over the decades, it evolved from a small-scale haunt into a massive production with hundreds of "scare actors," elaborate multi-sensory mazes, and "Scare Zones." The event famously pioneered the "sliding" technique—where actors wear metal kneepads to slide across the ground and create a loud, sparks-flying jump scare—setting the gold standard for the modern haunted attraction industry.