After the death of Shaggy's Uncle Beaureguard, he, Scooby and Scrappy arrive at the late uncle's Southern plantation to collect the inheritance. But as soon as they arrive, they find it is haunted by the ghost of a Confederate soldier. With this spook on their tails while they solve riddles in search of the inheritance, they seek help from the Boo Brothers, a trio of ghost-exterminators to help catch this nasty ghoul.

On his uncle's death Sir Henry Baskerville returns from Canada to take charge of his ancestral hall on the desolate moors of Devonshire, and finds that Sherlock Holmes is there to investigate the local belief that his uncle was killed by a monster hound that has roamed the moors since 1650, and is likely to strike again at Sir Henry.