 | John Gregson als Captain Bell - H.M.S. Exeter |
 | Anthony Quayle als Commodore Harwood - H.M.S. Ajax |
 | Ian Hunter als Captain Woodhouse - H.M.S. Ajax |
 | Jack Gwillim als Captain Parry - H.M.N. Z. S. Achilles |
 | Bernard Lee als Captain Dove - M.S. Africa Shell |
 | Lionel Murton als Mike Fowler |
 | Anthony Bushell als Sir Millington Drake, British Minister, Montevideo |
 | Peter Illing als Dr. Guani, Foreign Minister, Uruguay |
 | Michael Goodliffe als Captain McCall, R.N., British Naval Attache, Buenos Aires |
 | Patrick Macnee als Lieutenant Commander Medley, R.N. |
 | John Chandos als Dr. Langmann, German Minister, Montevideo |
 | Douglas Wilmer als M. Desmoulins, French Minister, Montevideo |
 | William Squire als Ray Martin |
 | Roger Delgado als Captain Varela, Uruguayan Navy |
 | Andrew Cruickshank als Captain Stubbs, 'Doric Star' |
 | Christopher Lee als Manolo |
| Edward Atienza als Pop |
| April Olrich als Dolores |
 | Peter Finch als Captain Langsdorff, "Admiral Graf Spee" |
 | David Farrar als Narrator |
 | Jeremy Kemp als Gunner, H.M.S. Achilles (uncredited) |
 | John Le Mesurier als Reverend George Groves - Padre, HMS Exeter |
 | Cyril Luckham als Lieutenant Jasper Abbot, H.M.S. Achilles |
 | Donald Moffat als Swanston, Lookout, H.M.S. Ajax (uncredited) |
| George Murcell als Chief Officer, Newton Beach |
 | Anthony Newley als Radio Operator, Tairoa, Prisoner on Admiral Graf Spee |
 | Nigel Stock als Chief Officer, Tairoa, Prisoner on Admiral Graf Spee |
 | Barry Foster als Bill Roper - Capt. Bell's Messenger, HMS Exeter |
 | Ambrosine Phillpotts als Mrs. Millington-Drake, Montevideo |
 | Tony Wager als Lookout, HMS Ajax |
 | Brian Worth als Radio Operator, Doric Star, Prisoner on Graf Spee |
| Patrick Westwood als Archer, HMS Ajax |
| Chris Adcock als British Seaman (Prisoner on Graf Spee) (uncredited) |
| Michael Collins als Chief Yeoman, HMS Ajax (uncredited) |
 | Patrick Jordan als Signalman, Aft-Conning, HMS Exeter (uncredited) |
| Jeremy Kemp als Gunner, HMS Achilles (uncredited) |
| Donald Moffat als Swanston - Lookout, HMS Ajax (uncredited) |
 | John Schlesinger als Lieutenant, Graf Spee (uncredited) |
| Richard Beale als Capt. Pottinger (uncredited) |
| John Forbes-Robertson als Lt. McBarnett, HMS Exeter (uncredited) |
| Emeric Pressburger | Director |
| Michael Powell | Director |
| Emeric Pressburger | Writer |
| Michael Powell | Writer |
| Brian Easdale | Original Music Composer |
| Arthur Lawson | Production Design |
| Michael Powell | Producer |
| Christopher Challis | Director of Photography |
| Emeric Pressburger | Producer |
| Reginald Mills | Editor |
| Jean Osborne | Publicist |
| John Brabourne | Production Manager |
| W. Edward Parry | Thanks |
| Betty Harley | Continuity |
| Charles Orme | Assistant Director |
| C. C. Stevens | Sound Recordist |
| Charles Woodhouse | Thanks |
| Sydney Streeter | Associate Producer |
| Bill Warrington | Special Effects |
| James Snow | Special Effects |
| Joan Harwood | Thanks |
| F.S. Bell | Technical Advisor |
| Don Picton | Assistant Art Director |
| Frederick Lewis | Music Director |
| Austin Dempster | Camera Operator |
| Geoffrey Rodway | Makeup Artist |
| Arthur Alcott | Production Controller |
| Patrick Dove | Technical Advisor |
| Arthur Stevens | Sound Editor |
| Gordon K. McCallum | Sound Recordist |
| Earl St. John | Executive Producer |
| F.S. Bell | Thanks |
| Patrick Dove | Thanks |
| Hein Heckroth | Other |
