When teen Sarah is forced to babysit her half-brother Toby, she summons Jareth the Goblin King to take him away. When he is actually kidnapped, Sarah is given just thirteen hours to solve a labyrinth and rescue him.

Scooby-Doo and Shaggy must go into the underworld ruled by The Goblin King in order to stop a mortal named The Amazing Krudsky who wants power and is a threat to their pals: Fred, Velma, and Daphne.

Underlying disorder in Jared and Amy's relationship comes to a head when Jared becomes monomaniacally obsessed with going Goblin Mode.