Overview

• The Netflix Original adult animated horror-comedy from creator and showrunner Matt Roller premiered Sept. 19 with all 10 episodes now streaming.
• Produced by Netflix Animation with executive producers Chris McKenna, Dan Harmon, and Steve Levy, the series blends family-sitcom dynamics with horror pastiches in ~24–25 minute installments.
• The story follows single mother Katherine running the haunted Undervale Hotel with her children and the ghost of her brother Nathan, joined by demon child Abaddon.
• The principal voice cast features Eliza Coupe, Will Forte, Skyler Gisondo, Natalie Palamides, and Jimmi Simpson, whose performance as Abaddon draws repeated praise in reviews.
• Critics are divided, with outlets like Mashable and FandomWire highlighting ambition and genre Easter eggs, while The Guardian and Den of Geek describe the series as forgettable or merely fine.