Secret Inc. has broken the case to top all cases! They’ve found Coco Diablo, the top of a famous ensemble criminal organization. With Coco and her kitty in jail, “Trick or Treat Scooby-Doo!” Secret Inc. feels that they can at long last partake in a break. Wrong! Out of nowhere, threatening doppelgänger apparitions of the Scooby group and most loved exemplary enemies appear in Coolsville to undermine Halloween. Presently it ultimately depends on the interfering children to expose the most recent rapscallion and save Halloween!