When the Boogey Man causes Grim to lose his powers, rank, and title in the Underworld Court for misusing his powers, he plots to seek out Horror's Hand and take over the world. It's up to Billy, Mandy, Irwin, and Grim to get to Horror's Hand before the Boogey Man does.
as Billy / Billybot / Harold / Pale Ghoulish Juror / Chippy the Squirrel (voice) (as Richard Horvitz)
as Mandy / Mandroid / Older Mandy / Milkshakes / Some Kid (voice)
as Grim / Sperg / Pirate #6
as Irwin / Pirate #5 / Unicorn (voice)
as I'll Cut You Guy / Pirate #2 / Horrorbot / Burnt Skeleton Guard (voice)
as Peequay (voice)
as Bride of Frankenstein (voice)
as Creeper / Horror's Hand / Pirate #3 / Paperboy (voice)
as Giant Cyclops / Ugly Pirate (voice)
as Fred Fredburger / Pirate #4 (voice)
as Billy's Mom (voice)
as Older Irwin (voice)
as Space Villain / Glacier of Evil / Dracula / Judge Roy Spleen / Underworld Cop (voice)
as 2 Headed Parrot (voice)
as Horror (voice)
as General Skarr / Pirate #7 (voice)
as Executioner / Pirate #1 (voice)
as Numbuh Three (voice)
as Pirate #8 / Miniature Cyclops / Spider Clown Mailman / Beast Master (voice)
as The Boogey Man (voice)