Colin Farrell as Steven Murphy

Nicole Kidman as Anna Murphy

Barry Keoghan as Martin Lang

Raffey Cassidy as Kim Murphy

Sunny Suljic as Bob Murphy

Bill Camp as Matthew Williams

Alicia Silverstone as Martin's Mother

Herb Caillouet as Ed Thompson (Hospital Director)

Barry G. Bernson as Dr. Larry Banks

Denise Dal Vera as Mary Williams

Drew Logan as Principal

Ming Wang as Doctor (Abdominal)

Michael Trester as Elderly Man

Anita Farmer Bergman as Nurse (uncredited)

Lea Hutton Beasmore as Conference Guest (uncredited)

Dylan Keith Adams as Doctor at Conference and Event Dinner (uncredited)

Charles Poole as Patient / Fisherman (uncredited)

John W. Harden as Conference Guest / Paramedic (uncredited)

Bryant Bentley as Paramedic (uncredited)

Aaron Pullins IV as Medical Conference Attendee (uncredited)

Joanne Popolin as Medical Conference Attendee (uncredited)

Carly Tamborski as Doctor at Conference (uncredited)

David Pittinger as Student's Dad (uncredited)

Michael Lee Bailey as Conference Guest (uncredited)

John Newsom as Doctor at Banquet (uncredited)

Robert Gerding as Visiting Consultant (uncredited)

William C. Ingram as Janitor (uncredited)

Beverly Kristy as Doctor (uncredited)

Derek Polen as Conference Guest (uncredited)

John E. Brownlee as Coastal Walker (uncredited)