James McAvoy

Dennis / Patricia / Hedwig / The Beast / Kevin Wendell Crumb / Barry / Orwell / Jade

Anya Taylor-Joy

Casey Cooke

Haley Lu Richardson

Claire Benoit

Jessica Sula

Marcia

Betty Buckley

Dr. Karen Fletcher

Izzie Coffey

Five-Year-Old Casey

Brad William Henke

Uncle John

Sebastian Arcelus

Casey's Father

Neal Huff

Mr. Benoit

Ukee Washington

News Anchor

Ann Wood

Game Show Enthusiast

Robert Michael Kelly

Joe