Brie Larson

Ma

Jacob Tremblay

Jack

Joan Allen

Nancy

Sean Bridgers

Old Nick

Tom McCamus

Leo

William H. Macy

Robert

Cas Anvar

Dr. Mittal

Amanda Brugel

Officer Parker

Wendy Crewson

Talk Show Hostess

Joe Pingue

Officer Grabowski

Matt Gordon

Doug

Zarrin Darnell-Martin

Attending Doctor

Jee-Yun Lee

News Anchor

Randal Edwards

Lawyer

Justin Mader

FBI Agent

Rodrigo Fernandez-Stoll

Reporter #2

Kate Drummond

Neighbour

Jack Fulton

Jack's Friend

Chantelle Chung

Clerk (uncredited)

Graeme Potts

TV Cameraman (uncredited)

Katelyn Wells

Teenage Girl (uncredited)

Celeste Bruno

Heather Noelle (uncredited)

Megan Park

Laura (uncredited)