Leah Lewis Ember (voice) Mamoudou Athie Wade (voice) Ronnie del Carmen Bernie (voice) Shila Ommi Cinder (voice) Wendi McLendon-Covey Gale (voice) Catherine O'Hara Brook (voice) Mason Wertheimer Clod (voice) Ronobir Lahiri Harold (voice) Wilma Bonet Flarrietta (voice) Joe Pera Fern (voice) Matthew Yang King Alan / Lutz / Earth Pruner (voice) Reagan To Big Kid Ember (voice) Jeff Lapensee Sparkler Customer (voice) Jonathan Adams Flarry (voice) Alex Kapp Customer / Delivery Person / Earth Landlord (voice) P.L. Brown Doorman (voice)