George Fan (originally white George Fayne) is played by Chinese-American Leah Lewis as an Asian woman managing the diner and dealing with family issues; Ned "Nick" Nickerson (originally white) is played by Black actor Tunji Kasim with a backstory involving law enforcement troubles. Bess Marvin, straight in the source material, is portrayed by British-Iranian Maddison Jaizani as a lesbian whose relationships drive subplots, including with Addy in season 3 after earlier arcs with Lisbeth and the lesbian ghost Odette possessing George in season 2.

Showrunners Noga Landau and Melinda Hsu Taylor prioritized a diverse cast and writers' room to reflect modern multi-ethnic America, with Ace's Jewish identity and Holocaust survivor references adding further layers in season 3. The core premise remains supernatural mysteries like the Frozen Hearts Killer and Temperance Hudson's occult threats, with personal relationships and sleuthing as the emotional drivers rather than identity politics lectures. These casting and character choices embed progressive representation centrally enough to elevate the score but do not make ideology the foundational narrative.