Ewan McGregor as Sam Foster

Naomi Watts as Lila Culpepper

Ryan Gosling as Henry Letham

Kate Burton as Mrs. Letham

Elizabeth Reaser as Athena

Bob Hoskins as Dr. Leon Patterson

BD Wong as Dr. Bradley Ren

Janeane Garofalo as Dr. Beth Levy

John Tormey as Custodian / Piano Mover #1

José Ramón Rosario as Cabbie / Piano Mover #2

Becky Ann Baker as Paramedic #1 / Butch Cook

Lisa Kron as Paramedic #2

Gregory Mitchell as Dance Instructor

John Dominici as Boy / Young Henry

Jessica Hecht as Boy's Mother

Sterling K. Brown as Frederick / Devon

Amy Sedaris as Toni

Michael Devine as Security Guard

Mark Margolis as Bookstore Owner

Jolly Abraham as Young Woman / Intern

Mary Testa as Waitress #1

Angela Pietropinto as English Woman / Waitress #2

Oni Faida Lampley as Daisy / Waitress #3

Jarlath Conroy as English Man

Michael Gaston as Sheriff Kennelly / Security Officer

Noah Bean as Clerk / Student Guide

Isaach de Bankolé as Professor

G.A. Aguilar as Bicyclyst

Riley G. Matthews, Jr. as Officer #1

Vito Violante as Officer #2

Douglas Crosby as Psych Ward Paramedic #1

Blaise Corrigan as Psych Ward Paramedic #2

Hank Eulau as Noodle Man

Mam Smith as Dancer #1

Caroline Vexler as Dancer #2

Joan Chiang as Dancer

Ron DeJesus as Dancer

Carolyn Dorfman as Dancer

Emily Gayeski as Dancer

Noel MacDuffie as Dancer

Kevin Osgood as Dancer

Elizabeth H. Parkinson as Dancer

Karine Plantadit as Dancer

John Selya as Dancer

Kyle Sheldon as Dancer

Tom Titone as Dancer

Pamela B. Wagner as Dancer

Amber Gristak as Accident Witness (uncredited)

Andrew Horne as Art Student (uncredited)

Jerry Quinn as Old Man in Diner (uncredited)