Leonardo DiCaprio

Self

Will Ferrell

George W. Bush

Faith Hill

Self

Dustin Hoffman

Self

Richard Jenkins

Self

Jenifer Lewis

Self

Julia Louis-Dreyfus

Self

Bill Maher

Self

Steve Martin

Self

Tim McGraw

Self

Virginia Newcomb

Self

Kevin Sateri

Self

Matthew Shaffer

Self

Ben Stiller

Self

Wanda Sykes

Self

William Wessley

Self

Robin Williams

Self

Meeghan Henry

Child (uncredited)

Jim Lovell

Self

Eric Idle

Self

Cohl Klop

Global Warming Protector

Robert Smigel

Triumph the Insult Comic Dog

Martin Short

Nathan Thurm

Robert F. Kennedy Jr.

Self

Conan O'Brien

Self

Ray Romano

Self

Kevin Nealon

Self

Dana Carvey

Self

Al Franken

Self

Jeffrey Tambor

Self

Rob Corddry

Self (archived footage)

David Letterman

Self (archived footage)