Luke Harrison's dad makes horror movies. It is a lot of fun being around a lot of such scary stuff - especially when you have your own monster museum at home. But when two ventriloquist dummies - Slappy and his twin Snappy join the collection, things get real creepy. Slappy and Snappy can walk and talk on their own. And they can make you scream on their own. They have a plan to make everyone's lives miserable. Will Luke be able to stop this terrible twosome?