George MacKay

Jack Marrowbone

Acting

Anya Taylor-Joy

Allie

Acting

Charlie Heaton

Billy Marrowbone

Acting

Mia Goth

Jane Marrowbone

Acting

Matthew Stagg

Sam Marrowbone

Acting

Nicola Harrison

Rose Marrowbone, Mother

Acting

Kyle Soller

Tom Porter

Acting

Tom Fisher

Simon Fairbairn, Father

Acting

Myra Kathryn Pearse

Molly

Acting

Paul Jesson

Doctor

Acting

Robert Strange

Monster

Acting

Laura Brook

Thelma (uncredited)

Acting

Adam Quintero

Mr. Gouldman (voice) (uncredited)

Acting