Warner Bros. is going all out this Halloween to bring you a new Scooby-Doo adventure that pits the mystery gang against the scourge of Gotham, Jonathan Crane aka The Scarecrow! However, Fred, Velma, Daphne, Shaggy, and Scooby are not alone in dealing with one of Batman's most dangerous foes. When it comes to the new animated movie Happy Halloween, Scooby-Doo!, they have in their corner such distinguished guests as Elvira, Mistress of the Dark, and Bill Nye, the Science Guy. You can read the synopsis for the film below.

"When toxic ooze brings the Crystal Cove pumpkin patch to life, it's up to Scooby-Doo (Frank Welker), Shaggy (Matthew Lillard), Daphne (Grey Griffin), Velma (Kate Micucci), and Fred (Welker) to save the day. And who's behind these high-flying jack-o-lanters and their king-sized pumpkin leader? Why, it's Doctor Jonathan Crane, aka Scarecrow (Dwight Schultz), a recent escapee from Arkham Asylum!"

The trailer for the movie reveals that trouble begins on All Hollow's eve when the Mystery Inc. runs into Elvira taking part in the festivities for the special day. Things quickly turn south when the celebrations are hijacked by a pumpkin-headed fiend, who is identified by Velma as an alter-ego of The Scarecrow.

Now, the gang, along with Elvira, must stop Scarecrow's deadly creations from wreaking havoc on the town. Special guest Bill Nye aids them in their work by offering them a souped-up Mystery Van with enough fancy gadgets and features to put the Batmobile to shame.

Cassandra Peterson rounds out the voice cast as Elvira. The film was written, produced, and directed by Maxwell Atoms - creator of Cartoon Network classics like Evil Con Carne and The Grim Adventures of Billy & Mandy. Sam Register (Ben 10, Batman: The Killing Joke, Gremlins: Secrets of the Mogwai) serves as executive producer.

As one of the longest-running and most popular franchises in Hollywood, Scooby and the gang are used to teaming up with a host of illustrious guest stars on their eternal journey solving one mystery after another. In fact, Mystery Inc. has crossed over with Batman as recently as 2018, for Scooby-Doo! & Batman: The Brave and the Bold to take on a variety of Gotham villains.

Now that Warner Bros. is gearing up to enter the world of streaming with HBO Max, it is likely that fans will get to see a lot more of such types of crossovers to appeal to as many fans as possible. In fact, the recently released SCOOB! was meant to be the start of the Hanna-Barbera Cinematic Universe, combining the world of Scooby and the gang with other classic characters from the legendary animation studio, including Blue Falcon and Dick Dastardly. Although since SCOOB! was met with middling reviews, it is debatable how many more entries we get to see in that particular series.

For now, Scooby fans can look forward to Happy Halloween, Scooby-Doo!, when it arrives on Digital and DVD this fall. This trailer dropped exclusively on Syfy.com.