Zac Efron as Jim Carrico

Marcia Gay Harden as Doris Nelson

Paul Giamatti as Abraham Zapruder

Billy Bob Thornton as Forrest Sorrels

Jacki Weaver as Marguerite Oswald

Ron Livingston as James Hosty

Jeremy Strong as Lee Harvey Oswald

James Badge Dale as Robert Oswald

Tom Welling as Roy Kellerman

Colin Hanks as Dr. Malcom Perry

Jackie Earle Haley as Father Oscar Huber

David Harbour as Gordon Shanklin

Paul Sparks as Harry McCormick

Mark Duplass as Kenneth O'Donnell

Rory Cochrane as Earl Rose

Matt Barr as Paul Mikkelson

Austin Nichols as Emory Roberts

Gil Bellows as David Powers

Jonathan Breck as Winston Lawson

Elizabeth Tulloch as Marilyn Sitzman

Dana Wheeler-Nicholson as Lillian Zapruder

Kat Steffens as Jacqueline Kennedy

Brett Stimely as President Kennedy

Sean McGraw as Lyndon B. Johnson

Jimmie Dale Gilmore as Reverend Saunders

Gary Grubbs as Dr. Kemp Clark

Bryan Batt as Malcolm Kilduff

Glenn Morshower as Mike Howard

Chuck Huber as Hugh Jamieson

Gary Clarke as Admiral George Burkley

Mallory Moye as Emergency Room Nurse

Jason Douglas as Ken Howe

Larry Jack Dotson as Acme Brick Supervisor

Nico Evers-Swindell as Rufus Youngblood

Irene White as Hospital Switchboard Operator #1

Luci Christian as Hospital Switchboard Operator #2

Ellen Halper as Acme Brick Timekeeper

Chris Freihofer as Chamberlain

Taylor Scorse as Nurse

Oryan Landa as Texas Ranger

Heath Allyn as Secret Service Agent (uncredited)

Sarah Joy Byington as Marina Oswald (uncredited)

John Cann as Secret Service Agent (uncredited)

Anthony J. Caruso as Secret Service Agent (uncredited)

Darryl Cox as Gen. Godfrey McHugh (uncredited)

Nathaniel Holt as Acme Brick Employee (uncredited)

Anne Lockhart as ER Nurse (uncredited)

Greg Wise as Doctor in Trauma Room (uncredited)

Jeff Gibbs as Kodak Lab Technician (uncredited)

Armando Gutierrez as Dallas Police Officer - Glen McBride (uncredited)