It's Halloween and a mysterious new enemy wants revenge against Mystery, Inc.
Now they'll have to team up with their arch-nemesis - the evil mastermind behind
every costume in Scooby-Doo history - to solve this macabre mystery. With this
unpredictable new ally, Scooby and friends will learn some spooky new tricks and
even don the outfits of their most famous foes to save the day on this special
Halloween night.