The movie involves Batman teaming up with the Scooby Doo gang when villains from both of their worlds unite to wreak havoc on the city. In addition to classic DC villains like the Joker, Catwoman, Harley Quinn, the Riddler, and so forth, alongside heroes like Aquaman, Black Canary, and Plastic Man, the film also has classic Scooby Doo villains in it, like the Ghost Clown, the Space Kook, and the Miner 49er.