Sonny is a curious science-loving kid. With his best friend Sam, he has heaps of adventures. Sonny’s curiosity can sometimes lead to trouble… just like in this movie!
Sarah is Sonny’s big sister. She’s very smart and is applying for university. The boys enlist her wise leadership to help defeat Slappy and save Wardenclyffe, their hometown. Sam is Sonny’s best friend and he’s very good at organising their adventures. The pair even run their own business cleaning up other people’s junk, hoping to find treasure. They certainly found something this time!
Slappy is a creepy ventriloquist’s doll who can move and speak on his own. He’s one of the most popular villains from the classic Goosebumps book series, appearing in a whopping 10 books. When Sonny and Sam accidentally release him, his spell causes all the Halloween decorations in town to turn into real monsters! Goblins, witches and werewolves, oh my!