Kevin Costner

Kenneth O'Donnell

Bruce Greenwood

John F. Kennedy

Steven Culp

Robert F. Kennedy

Dylan Baker

Robert McNamara

Michael Fairman

Adlai Stevenson

Henry Strozier

Dean Rusk

Frank Wood

McGeorge Bundy

Kevin Conway

Gen. Curtis LeMay

Tim Kelleher

Ted Sorensen

Len Cariou

Dean Acheson

Bill Smitrovich

Gen. Maxwell Taylor

Shawn Driscoll

U-2 Pilot

Stephanie Romanov

Jacqueline Kennedy

Lucinda Jenney

Helen O'Donnell

Caitlin Wachs

Kathy O'Donnell

Jon Foster

Kenny O'Donnell, Jr.

Bruce Thomas

Floyd

Dakin Matthews

Arthur Lundahl

Colette O'Connell

Kenny's Assistant #2

Karen Ludwig

Operator Margaret

Audrey Rapoport

White House Operator #1

Marliese Schneider

White House Operator #2

Ed Lauter

Gen. Marshall Carter

James Karen

George Ball

Dan Ziskie

Gen. Walter 'Cam' Sweeney

Peter White

John McCone

Kelly Connell

Pierre Salinger

Olek Krupa

Andrei Gromyko

Elya Baskin

Anotoly Dobrinyn

Timothy Jerome

Journalist

Jack McGee

Richard J. Daley

John Aylward

Orville Dryfoos

Madison Mason

Adm. George Anderson

Christopher Lawford

Cmdr. William B. Ecker

David O'Donnell

Lt. Bruce Wilhemy

Benjamin Koldyke

RF-8 Pilot

Thomas Roberts

Sonar Operator

Michael Gaston

Captain of USS Pierce

J. Tucker Smith

Captain of USS Kennedy

Chris Henry Coffey

Officer of Destroyer

Oleg Vidov

Valerian Zorin

Alex Veadov

Radio Room Operator #3

Jack Blessing

John Scali

Tom Everett

Walter Sheridan

Karl Makinen

Young FBI Agent

Boris Lee Krutonog

Alexander Fomin

Charles Esten

Maj. Rudolf Anderson

Allan Graf

Football Referee

Robert Miranda

RFK's Driver

Cliff Fleming

Aerial Coordinator

Craig Hosking

Pilot

Greg Bronson

Secret Service Agent (uncredited)

Walter Cronkite

Self (archive footage) (uncredited)

Ryder Davis

Boy Scout (uncredited)

Armen Garo

Crewman on Freighter (uncredited)

Phil Hawn

UN Administrator (uncredited)

Ted Hollis

OAS Delegate (uncredited)

Rick Kain

Carpenter (uncredited)

John F. Kennedy

Self (voice) (archive footage) (uncredited)

Pramod Kumar

U Thant (uncredited)

Richard Rossi

Reporter (uncredited)

Brad Yoder

Sorensen's Assistant (uncredited)