Kiefer O'Reilly as Howard Lovecraft (Voice)

Jeffrey Combs as H.P. Lovecraft (voice)

Tyler Nicol as Winfield Lovecraft (voice)

Michelle O'Reilly as Sarah Lovecraft (voice)

Sean Patrick O'Reilly as Spot / Cthulhu (voice)

Alison Wandzura as Mary Lovecraft (voice)

Mark Hamill as Dr. Henry Armitage (voice)

Vijary Vaibhav Saini as Professor Jaswant Atwood (voice)

Ashleigh Ball as Ellen Ellery (voice)

Scott McNeil as Hamish Rice / Govlins (voice)

Nick Wolfhard as William Dyer (voice)

Christopher Plummer as Dr. Jeffrey West (voice)

Finn Wolfhard as Herbert West (voice)

Doug Bradley as Nyarlathotep (voice)

Summer O'Reilly as Gotha (voice)

Harmony O'Reilly as Innes (voice)

Phoenix O'Reilly as Twi'i (voice)