Tom Cruise

Character: Frank T.J. Mackey

Philip Baker Hall

Character: Jimmy Gator

Philip Seymour Hoffman

Character: Phil Parma

Julianne Moore

Character: Linda Partridge

William H. Macy

Character: Quiz Kid Donnie Smith

John C. Reilly

Character: Officer Jim Kurring

Melora Walters

Character: Claudia Wilson Gator

Jeremy Blackman

Character: Stanley Spector

Jason Robards

Character: Earl Partridge

Melinda Dillon

Character: Rose Gator

Michael Bowen

Character: Rick Spector

April Grace

Character: Gwenovier

Ricky Jay

Character: Burt Ramsey / Narrator

Emmanuel Johnson

Character: Dixon

Pat Healy

Character: Sir Edmund William Godfrey / Young Pharmacy Kid

Genevieve Zweig

Character: Mrs. Godfrey

Mark Flanagan

Character: Joseph Green

Neil Flynn

Character: Stanley Berry

Rod McLachlan

Character: Daniel Hill

Allan Graf

Character: Firefighter

Patton Oswalt

Character: Delmer Darion

Raymond 'Big Guy' Gonzales

Character: Reno Security Guard

Brad Hunt

Character: Craig Hansen

Jim Meskimen

Character: Forensic Scientist

Chris O'Hara

Character: Sydney Barringer

Clement Blake

Character: Arthur Barringer

Frank Elmore

Character: 1958 Detective

John Kraft Seitz

Character: 1958 Policeman

Cory Buck

Character: Young Boy

Tim Soronen

Character: Infomercial Guy

Jim Ortlieb

Character: Middle-Aged Guy

Thomas Jane

Character: Young Jimmy Gator

Holly Houston

Character: Jimmy's Showgirl

Benjamin Niedens

Character: Little Donnie Smith

Veronica Hart

Character: Dentist Nurse #1

Missy Spell Tanner

Character: Dentist Nurse #2

James Kiriyama-Lem

Character: Dr. Lee

Jake Cross

Character: Pedestrian #1

Charlie Scott Jr.

Character: Pedestrian #2

Juan Medrano

Character: Nurse Juan

John Pritchett

Character: Police Captain

Cleo King

Character: Marcie

Don McManus

Character: Dr. Landon

Michael Shamus Wiles

Character: Captain Muffy

Jason Andrews

Character: Doc

John S. Davies

Character: Cameraman

Kevin Breznahan

Character: Geoff, Seminar Guy

Miguel Pérez

Character: Avi Solomon

Alfred Molina

Character: Solomon Solomon

David Masuda

Character: Coroner Man

Neil Pepe

Character: Officer #1

Lionel Mark Smith

Character: Detective

Annette Helde

Character: Coroner Woman

Lynne Lerner

Character: Librarian

Felicity Huffman

Character: Cynthia

Scott Burkett

Character: WDKK Page #1

Bob Brewer

Character: Richard's Dad

Julie Brewer

Character: Richard's Mom

Nancy Marston

Character: Julia's Mom

Maurey Marston

Character: Julia's Dad

Jamala Gaither

Character: WDKK P.A.

Danny Wells

Character: Dick Jennings

Amy Brown

Character: WDKK Page #2

Eileen Ryan

Character: Mary

Meagen Fay

Character: Dr. Diane

Patricia Forte

Character: Mim

Luis Guzmán

Character: Luis

Patrick Warren

Character: Todd Geronimo

Orlando Jones

Character: Worm

Virginia Pereira

Character: Pink Dot Girl (voice)

Craig Kvinsland

Character: Brad the Bartender

Patricia Scanlon

Character: Cocktail Waitress

Henry Gibson

Character: Thurston Howell

Natalie Elizabeth Marston

Character: Julia

Bobby Brewer

Character: Richard

Clark Gregg

Character: WDKK Floor Director

Art Frankel

Character: Old Pharmacist

Matt Gerald

Character: Officer #2

Guillermo Melgarejo

Character: Pink Dot Guy

Paul F. Tompkins

Character: Chad (Seduce & Destroy) (voice)

Mary Lynn Rajskub

Character: Janet (Frank's Assistant) (voice)

Jim Beaver

Character: Smiling Peanut Patron #1

Ezra Buzzington

Character: Smiling Peanut Patron #2

Denise Woolfork

Character: Smiling Peanut Patron #3

Michael Murphy

Character: Alan Kligman, Esq.

Robert Downey Sr.

Character: WDKK Show Director

William Mapother

Character: WDKK Show Director's Assistant

Larry Ballard

Character: WDKK Medic

Brett Higgins

Character: Mackey Disciple Twin #1

Brian Higgins

Character: Mackey Disciple Twin #2

Michael Lee Phillips Jr.

Character: Mackey Disciple in Middle

Lillian Adams

Character: Donnie's Old Neighbor

Steven Bush

Character: Paramedic #1

Mike Massa

Character: Paramedic #2

Dale Gibson

Character: Paramedic #3

Scott Alan Smith

Character: E.R. Doctor

Paul Thomas Anderson

Character: Man Confiscating Sign (uncredited)

Miriam Margolyes

Character: Faye Barringer (uncredited)

Bruno Angelico

Character: Fireman #2 (uncredited)

Robert Bella

Character: Detective #2 (uncredited)

Greg Bronson

Character: Waiter (uncredited)

Douglas Busby

Character: Extra (uncredited)

Marc Davies

Character: Seminar Attendee #1 (uncredited)

Bruce Gregory

Character: Randy (uncredited)

Phil Hawn

Character: Bob (uncredited)

Spencer Kayden

Character: Seminar Patron (uncredited)

Brian Kehew

Character: Seminar Patron (uncredited)

Michael Laren

Character: Officer Tom 1958 (uncredited)

Aimee Mann

Character: Hot Date Infomercial (uncredited)

Tom Ohmer

Character: Detective (uncredited)

Colleen Pelletier

Character: Gameshow Audience Member (uncredited)

Herb Santos Jr.

Character: 21 Dealer (uncredited)

Tom Tangen

Character: Drunken Dart Player (uncredited)