Samara Weaving was cast as June 27, but stepped down as scheduling conflicts and replaced by Jessica Rothe
Famke Janssen and Bill Skarsgard both starred in the tv series Hemlock Grove she played his mom
Pete Davidson was originally considered for the role of Boy.
A previous version of this film had Bill Skarsgard providing his own voiceover for his character in the style of a Mortal Kombat announcer before H. Jon Benjamin was cast for the final version; the trailer featuring Skarsgard's voiceover has mostly been scrubbed from the internet. In the original concept trailer, Boy's inner voice is taken from a cigarette commercial, with a voice similar to Sam Elliott's.