Mystery Inc. withdraws from solving crimes after botching a case. When Vincent Van Ghoul contacts the gang about an unfinished investigation from Daphne, Shaggy and Scooby's past, the gang springs into action to finish the job that involves catching the 13th Ghost that escaped from the Chest of Demons and is still at large.

A secret has returned from the past!

Mystery Inc. withdraws from solving crimes after botching a case. When Vincent Van Ghoul contacts the gang about an unfinished investigation from Daphne, Shaggy and Scooby's past, the gang springs into action to finish the job that involves catching the 13th Ghost that escaped from the Chest of Demons and is still at large.