Joaquin Phoenix Beau Wassermann
Paul Thomas Anderson Thanks
Parker Posey Elaine Bray
David Fincher Thanks
Bill Hader Thanks, UPS Guy
Amy Ryan Grace
Stephen McKinley Henderson Therapist
Marc-André Brisebois Comatose Junkie
Zoe Lister-Jones Young Mona
Richard Kind Dr. Cohen
Jorge Cañada Escorihuela VFX Supervisor
Rooney Mara Thanks
Tristan D. Lalla Costume Designer Orphan
Kylie Rogers Toni
Hayley Squires Penelope
Ari Aster Director, Producer, A Neighbor of Beau's (uncredited), Writer
Geoffroy St-Hilaire "A" Camera Operator, Steadicam Operator
Julian Richings Strange Man
Patti LuPone Mona Wassermann
Nathan Lane Roger
David Mamet Rabbi
Spike Jonze Thanks
Archie Madekwe Laughing Man
Théodore Pellerin Beau’s Son
Tyrone Benskin Rattled Businessman
Marko Costanzo Foley Artist
David McKeown Stunt Coordinator
Michael Gandolfini Beau’s Son
Bo Burnham Thanks
Renato De Cotiis Second Assistant Director
Ryan S. Hill Hero Beau's Young Son
Véronique Marchessault Assistant Costume Designer
Lorene Scafaria Thanks
Lars Knudsen Producer
Denis Ménochet Jeeves
Michael Esper Officer Johnson
Billy Mayo In Memory Of
Arthur Holden Duncan / God on Cloud / Hero Beau’s Wife
Gord Robertson Monster Puppeteer
Joe Cobden News Correspondent (Brian Galloway)
Ruben Östlund Thanks
Kwasi Songui Orphan Ladybug Man
Peter Seaborne Ceiling Man
Teddy Blanks Title Designer
Paul Hsu Supervising Sound Editor, Sound Re-Recording Mixer
Lily Bird Samanda
Steve Newburn Prosthetic Designer, Monster Puppeteer
Alex Bisping Orphan Production Designer
Maev Beaty Angel / Play Narrator
Louis Craig Special Effects Supervisor
Len Blavatnik Executive Producer
Bradley Fisher Birthday Boy Stab Man
Catherine Bérubé Hero Beau's Wife
Stephanie Herrera Martha
Yuval Levy Visual Effects Supervisor
Hélèna Laliberté Stunt Driver
Cat Lemieux Orphan Chorus Member
Armen Nahapetian Teen Beau
Harry Standjofski Superintendent / Catering Manager
Patrick Kwok-Choon Orphan Hero
Chris Carroll First Assistant Director
Julia Antonelli Teen Elaine
Claude La Haye Production Sound Mixer
Louis Morin Visual Effects Supervisor
Dave Flynch Foley Supervisor
Luis Oliva Crust Punk (Eyes Gouged)
Luca Borghese Co-Producer
Alex Stines Stunts
Elizabeth Tremblay Script Supervisor
Timo Argillander Executive Producer
Melissa Fafard Makeup Artist
David Gaucher Supervising Art Director