Plot
When his vehicle breaks down outside Hayesville, Nevada, a quiet drifter is picked up by local mechanic Jed Love, who takes him to Willy's Wonderland, a once-successful abandoned family entertainment center inhabited by eight now-withered animatronic mascots: Willy Weasel, Arty Alligator, Cammy Chameleon, Ozzie Ostrich, Tito Turtle, Knighty Knight, Gus Gorilla, and Siren Sara.
The restaurant's owner Tex Macadoo offers him work as a night-shift janitor in exchange for repairing his vehicle before he and Jed leave him locked inside it. Meanwhile, teenager Liv Hawthorne attempts to burn down the restaurant but she gets handcuffed by her guardian, Hayesville's sheriff Eloise Lund. After Lund leaves, Liv is freed by her friends Chris, Kathy, Aaron, Bob, and Dan.
As the Janitor begins his duties, the animatronics are revealed to be sentient and homicidal. Ozzie attacks him but is beaten to death with a mop. Liv enters the restaurant through the vents to get the Janitor out while her friends douse the perimeter with gasoline. Simultaneously, the Janitor is attacked by Gus in the restrooms; he fatally curb stomps Gus's face into a urinal. Arty chases Liv but she escapes into a fairy-themed room where Sara attacks her. Liv manages to fend off Sara and encounters the Janitor, who ignores her warnings about the animatronics and refuses to leave.
Outside, Liv's friends climb to the roof, which collapses and causes them to fall inside. Liv explains to the Janitor that the restaurant was originally owned by notorious serial killer Jerry Robert Willis. He and his seven cannibalistic colleagues slaughtered unsuspecting families, but the authorities eventually discovered them. They performed a satanic ritual to transfer their souls into the animatronics before committing suicide. When Liv finishes, several animatronics awaken and attack the group.
In the ensuing chaos, Knighty fatally impales Aaron with his sword, Dan is eaten alive by Tito and Sara, and Arty mauls Kathy and Bob to death in a party room. Just before Knighty can kill Liv, the Janitor decapitates him and also breaks Arty's jaws, killing them both. As Cammy stalks Chris in an arcade, he calls Lund for help; she goes to the restaurant with deputy sheriff Evan Olson upon learning that Liv is there.
On the way, Lund reveals to Evan that, after the restaurant was shut down, the animatronics continued murdering people around Hayesville until she, Tex, and Jed made a deal with them. Over the years, they tricked random drifters into cleaning up the restaurant, offering them as human sacrifices in order to stop the animatronics' killing spree. Liv's parents were among the victims and a guilty Lund adopted her. When the Janitor and Liv arrive at the arcade, Cammy snaps Chris's neck. They subdue Cammy and attempt to leave before Lund and Evan stop them. Lund handcuffs the Janitor and leaves him to die as Evan takes Liv away. While driving back, Evan is killed by a stowaway Tito as Liv escapes.
In the restaurant, the Janitor subdues Sara and fatally twists Cammy's head. An enraged Lund tries to lure Willy to kill the Janitor, only for Willy to tear her in half. Willy and the Janitor fight each other until the Janitor kills him by hitting his face repeatedly with a bag filled with soda cans and ripping his head off. The next morning, Tex and Jed return and find the restaurant completely clean, with the animatronics missing. The Janitor receives his repaired vehicle and invites Liv to accompany him. While Tex and Jed discuss planning to re-open the restaurant, Sara suddenly appears, and sets their car on fire with gasoline, causing a massive explosion that kills the three. As the sun rises, the Janitor and Liv drive out of the town, running over a wandering Tito along the way.
