Rainbow Brite, and her magical horse Starlite, must stop an evil princess and her underlings from taking over the planet Spectra. When they meet Orin, the wise Sprite tries to make the two children get along and work together to stop the evil Princess. Orin tells them that they can only destroy her by combining their own powers against her. Getting in the way of their mission is the sinister Murky Dismal and his bumbling assistant Lurky who, as usual, are lavishing in the new gloom created by the darkening of Spectra, as well as trying to steal Rainbow's magical color belt.
Bettina Bush
as Rainbow Brite (voice) (as Bettina)
Pat Fraley
as Lurky / On-X / Buddy Blue / Dog / Guard / Spectran / Slurthie / Glitterbot (voice) (as Patrick Fraley)
Peter Cullen
as Murky Dismal / Castle Monster / Glitterbot / Guard / Skydancer / Slurthie (voice)
Robbie Lee
as Twink / Shy Violet / Indigo / La La Orange / Spectran / Sprites (voice)
Andre Stojka
as Starlite / Wizard / Spectran (voice)
David Mendenhall
as Krys (voice)
Rhonda Aldrich
as The Princess / The Creature (voice)
Les Tremayne
as Orin / Bombo / TV announcer (voice)
Mona Marshall
as Red Butler / Witch / Spectran / Castle Creature / Patty O'Green / Canary Yellow (voice)
Jonathan Harris
as Count Blogg (voice)
Marissa Mendenhall
as Stormy (voice)
Scott Menville
as Brian (voice)
