Characters played by George MacKay
Jack
Characters played by Anya Taylor-Joy
Allie
Characters played by Charlie Heaton
Billy
Characters played by Mia Goth
Jane
Characters played by Matthew Stagg
Sam
Characters played by Nicola Harrison
Mother
Characters played by Kyle Soller
Porter
Characters played by Tom Fisher
Father
Characters played by Myra Kathryn Pearse
Molly
Characters played by Paul Jesson
Doctor
Characters played by Robert Nairne
Monster