Warner Bros. Has been getting a lot of hate lately after the Warner Discovery, and Trick or Treat Scooby-Doo is the lone DTV Scooby movie of the year (making it sad, especially since WB made the stupid move to cancel a holday special based on the Scoob movie that was almost completed and write it off as a tax cut, meaning money that could've been made moving that to DTV being thrown to the flaming dumpster on the studio lot). Anyway, after breaking their biggest case of all, the Mystery Inc gang have been reduced to doing odd jobs since they busted Coco Diablo, who has been providing costumes for the villains they have chased over the years. One year later, Fred decides to set up a booth at the Coolsville Halloween Festival in hopes of getting a real mystery, however, he soon gets his wish as the gang allow Coco Diablo to join them in their latest mystery, involving ghosts who look just like them.
Okay, Happy Halloween Scooby-Doo was a movie I liked as it basically redeemed the film series after the last two films were negatively received (mainly for the sin of changing continuity because Warner Bros. Wants to keep the films like the 1969 series that started it all). However, Trick or Treat manages to commit that sin with the Coco Diablo character, who in the film, was introduced as a criminal mastermind who not only made the Cat Man monster suit for the opening scene, but also the costumes of the Black Knight, Space, Kook, Ghost Clown, and six others from the original show. Once again, Warner Bros. Messes with Scooby-Doo's continuity all because they want to add another character in, and here, they claim the crooks of those nine episodes got their costumes from her (when the original series showed they made their own costumes for their notorious deeds (as Mr. Whitler wore the Black Knight armor and it was delivered to the museum, and Captain Cutler's diving suit had glowing seaweed to make him look like a ghost). I get adding a character making costumes from the various rogues, but it should not be done at the expense of changing what fans of the Great Dane already appreciate.
Another problem is the writing. Seriously, while it was good to see all the villains Scooby and the gang have busted, it is sadly bogged down by characters whose personalities are horrible (the Warden of the prison Coco is in is a fanboy who is okay with them), and the whole story feels like it has less effort put in the writing compared to past Scooby DTV mysteries. Also, at 67 minutes, this feels more like an hour-long TV special than an actual direct-to-video movie, and while it was good to see the gang dress up in the monster costumes near the end, sadly, it was for a weak reason I shall not spoil. Only gets three stars from me for the cameos and the animation being decent, but the writing and continuity changes really makes this more of a trick than a treat for Scooby fans.
