"Witness The Unspeakable! Billy and Mandy Encounter The Space Invaders"
Alien werewolves from the Moon attack Earth and steal all the cheese. It's up to Mandy, Grim, Billy, and Sperg to stop the alien ploy.
Mandy / Castigator (voice)
Grim / Sperg (voice)
Billy / Billy's Dad (voice)
Irwin / Mouse (voice)
Alien Moonbeast / Alien Werewolf / Moonthing (voice)
Alien #1 / Rat (voice)
Meadowberry / Corporal / Postal Slob (voice)
Billy's Mom / Stinky (voice)
Dr. Brainiac / Alien Pilot / Wiggly / Waiter (voice)
Alien #2 (voice)
Sir Raven (voice)
