Haley Joel Osment
David

Jude Law
Gigolo Joe

Frances O'Connor
Monica Swinton

Sam Robards
Henry Swinton

Jake Thomas
Martin Swinton

William Hurt
Prof. Hobby

Jack Angel
Teddy (voice)

Robin Williams
Dr. Know (voice)

Ben Kingsley
Specialist (voice)

Meryl Streep
Blue Mecha (voice)

Chris Rock
Comedian (voice)

Ken Leung
Syatyoo-Sama

Clark Gregg
Supernerd

Kevin Sussman
Supernerd

Tom Gallop
Supernerd

Eugene Osment
Supernerd

April Grace
Female Colleague

Matt Winston
Executive

Sabrina Grdevich
Sheila

Theo Greenly
Todd

Michael Mantell
Dr. Frazier at Cryogenic Institute

Keith Campbell
Roadworker

Brian Turk
Backstage Bull

Brendan Gleeson
Lord Johnson-Johnson

Tim Rigby
Yeoman

Enrico Colantoni
The Murderer

Adrian Grenier
Teen in Van

Matt Malloy
Robot Repairman

Brent Sexton
Russell

Erik Bauersfeld
Gardener (Voice)

Michael Fishman
Teen in Van

Diane Fletcher
Sentient Machine Security

Al Jourgensen
Flesh Fair Band Member

Rena Owen
Ticket Taker

Adam Alexi-Malle
Crowd Member

Laurence Mason
Tech Director

Ashley Scott
Gigolo Jane

Miguel Pérez
Robot Repairman

Wayne Wilderson
Comedian

Eliza Coleman
General Circuita

Jim Jansen
Chef

Tim Rhoze
Laboratory Technician

Clara Bellar
FemMecha Nanny

Michael Shamus Wiles
Cop

J. Alan Scott
Worker

Lily Knight
Voice in the Crowd (voice)

Justina Machado
Assistant

Daveigh Chase
Child Singer (scenes deleted)

Kathryn Morris
Teenage Honey

Hunter King
Amanda

Michael Berresse
Stage Manager

Paula Malcomson
Patricia in Mirrored Room

John Prosky
Mr. Williamson, the Bellman