George MacKay character Jack Marrowbone
Anya Taylor-Joy character Allie
Charlie Heaton character Billy Marrowbone
Mia Goth character Jane Marrowbone
Matthew Stagg character Sam Marrowbone
Kyle Soller character Tom Porter
Tom Fisher character Simon Fairbairn, Father
Nicola Harrison character Rose Marrowbone, Mother
Myra Kathryn Pearse character Molly
Paul Jesson character Doctor
Robert Nairne character Monster
Laura Brook character Thelma (uncredited)
Adam Quintero character Mr. Gouldman (voice) (uncredited)
