Melissa Leo as Madalyn Murray O'Hair

Josh Lucas as David Waters

Michael Chernus as Jon Garth Murray

Rory Cochrane as Gary Karr

Vincent Kartheiser as William J. Murray III

Adam Scott as Jack Ferguson

Juno Temple as Robin Murray O'Hair

Sally Kirkland as Lena Christina

Brandon Mychal Smith as Roy Collier

Alex Frost as Danny Fry

Peter Fonda as Reverend Harrington

José Zúñiga as Detective Campos

Marco Sanchez as Frank Gonzalez

Ryan Cutrona as Pup

Anthony Vitale as Mark Sparrow

Ward Roberts as Leon Penski

David Gueriera as Bob Fry

Anna Camp as Mrs. Lutz

Andy Walken as Young Bill Jr.

David Henry Begin as Young Jon Garth

Lynn Telzer as Teen Susan

Vivienne Taylor as Prayer Girl

Alycen Malone as 50's Housewife #1

Frankie Sims as AA Member

Vernon Courteaux as Atheist

Danya LaBelle as FBI Agent Smith