The film, which will be called "Scoob," will be out in May 2020.
Will Forte was previously announced as Shaggy (sorry, Matthew Lillard), with Gina Rodriguez as Velma, and longtime-Scooby-Doo voicer Frank Welker returning as Scooby himself.
In the new movie, the Scooby gang will team up with other characters in the Hanna-Barbera universe to save the world from the evil Dick Dastardly. Tracy Morgan will voice another classic Hanna-Barbera character, Captain Caveman.
It'll be the first team up for the "Mean Girls" and "High School Musical" alums.