| Kevin Costner | Kenny O'Donnell, Special Assistant to the President |
| Bruce Greenwood | President John F. Kennedy |
| Steven Culp | Atty. Gen. Robert F. Kennedy |
| Dylan Baker | Robert McNamara, Secretary of Defense |
| Michael Fairman | Adlai Stevenson, US Ambassador to the UN |
| Henry Strozier | Dean Rusk, Secretary of State |
| Frank Wood | McGeorge Bundy, National Security Advisor |
| Kevin Conway | Gen. Curtis LeMay, Air Force Chief of Staff |
| Tim Kelleher | Ted Sorensen, Special Counsel to the President |
| Len Cariou | Dean Acheson, Foreign Policy Advisor |
| Bill Smitrovich | Gen. Maxwell D. Taylor, Chairman Joint Chiefs of Staff |
| Dakin Matthews | Arthur Lundhal |
| Madison Mason | Adm. George Anderson |
| Christopher Lawford | Cmdr. William B. Ecker, Mission Flight Leader |
| Ed Lauter | Lt. Gen. Marshall Carter |
| Elya Baskin | Anotoly Dobrynin, Soviet Ambassador |
| Boris Lee Krutonog | Alexander Fomin, KGB Agent |
| Peter White | John McCone, CIA Director |
| James Karen | George Ball, Undersecretary of State |
| Olek Krupa | Andrei Gromyko, Soviet Foreign Minister |
| Lucinda Jenney | Helen O'Donnell |
| Oleg Vidov | Valerian Zorin, Soviet Ambassador to the UN |
| Shawn Driscoll | U-2 Pilot |
| Drake Cook | Mark O'Donnell |
| Caitlin Wachs | Kathy O'Donnell |
| Jon Foster | Kenny O'Donnell, Jr. |
| Matthew Dunn | Kevin O'Donnell |
| Kevin O'Donnell | NPIC Photo Interpreter |
| Janet Coleman | Evelyn Lincoln, JFK's Secretary |
| Bruce Thomas | Floyd |
| Stephanie Romanov | Jacqueline Kennedy |
| Liz Sinclair | Kenny's Assistant #1 |
| Colette O'Connell | Kenny's Assistant #2 |
| Karen Ludwig | Operator Margaret |
| Timothy Jerome | Journalist |
| Audrey Rapoport | White House Operator #1 |
| Marliese Schneider | White House Operator #2 |
| Walter Adrian | Vice President Lyndon B. Johnson |
| Dan Ziskie | Gen. Walter 'Cam' Sweeney |
| Kelly Connell | Pierre Salinger, White House Press Secretary |
| Jack McGee | Richard J. Daley, Mayor of Chicago |
| Lamar Smith | Aide |
| John Aylward | Orville Dryfoos, New York Times Publisher |
| Vivien Straus | White House Aide |
| David O'Donnell | Lt. Bruce Wilhemy, Cmdr. Ecker's Wingman |
| Gene Del Bianco | Petty Officer |
| Benjamin Koldyke | RF-8 Pilot |
| Daniel Vergara | OAS President |
| Ruben Moreno | Argentine Diplomat |
| Thomas Roberts | Sonar Operator |
| Sean Bergin | Chief Sonarman |
| Alan Francis | Executive Officer of USS Pierce |
| Robert Munstis | Radio Room Operator #1 |
| Michael Gaston | Captain of USS Pierce |
| Joseph Repoff | Radio Room Operator #2 |
| J. Tucker Smith | Captain of USS Kennedy |
| Chris Henry Coffey | Officer of Destroyer |
| Radu Gavor | Romanian Delegate |
| Zitto Kazann | Chilean Delegate |
| Alex Veadov | Radio Room Operator #3 |
| Jack Blessing | John Scali |
| Tom Everett | Walter Sheridan, FBI |
| Karl Makinen | Young FBI Agent |
| Charles Esten | Maj. Rudolph Anderson |
| Charles Barrett | Air Force NCO |
| Darryl Smith | Football Coach |
| Allan Graf | Football Referee |
| Robert Miranda | RFK's Driver |
| Todd Sible | RFK's Staffer |
| Marya Kazakova | Soviet Woman |
| Cliff Fleming | Aerial Coordinator |
| Craig Hosking | Pilot |
| Walter Cronkite | Himself |
| Paul Farber | Child Greeting President |
| Phil Hawn | UN Administrator |
| John F. Kennedy | Himself |
| John Michael | UN Manager |
| Ryan Notch | Boy Scout |
| Richard Rossi | Reporter |
| Larry Strauss | Treasury Secretary Douglas Dillon |
| Ron A. Williams | Man Walking in Building |
| Brad Yoder | Sorensen's Assistant |
| Jennifer D. Lac Kamp | UN Secretary |
| Marie Tringali | UN Administrator |
| Hope Cruickshank | Kenny O'Donnell's Daughter |
| Tess Cruickshank | Kenny O'Donnell's Daughter |
| Sierra Farber | Child Greeting President |
