Attack of the Vampire Pumpkinheads play Attack of the Vampire Pumpkinheads What's New Scooby-Doo Help Scooby free the gang from a pack of possessed pumpkins! Message Board · Log on now and talk about this show! ...Mystery, Inc. is a group of teenagers and a dog who travel in the Mystery Machine solving mysteries. Getting in the way are a host of ghosts, monsters, vampires, and all kinds of creatures ready to scare off Shaggy and his pup, Scooby-Doo. Watch Scooby-Doo and play tons of free online games from the show on Cartoon Network.