Peter Sellers
Grand Duchess Gloriana XII / Prime Minister Count Rupert Mountjoy / Tully Bascombe
William Hartnell
Will Buckley
David Kossoff
Professor Alfred Kokintz
MacDonald Parke
General Snippet
Austin Willis
United States Secretary of Defense
Alan Gifford
Air Raid Warden
Colin Gordon
BBC Announcer
Guy Deghy
Soviet Ambassador (uncredited)
Eve Eden
Spectator (uncredited)
Bill Edwards
Army Captain (uncredited)
Mabel Etherington
Ada - Lady in Waiting (uncredited)
Muriel Greenslade
Lady in Waiting (uncredited)
Fred Haggerty
Fenwickian (uncredited)
Juba Kennerley
Maybury (uncredited)
George Margo
O'Hara (uncredited)
Lionel Murton
American General at the Pentagon (uncredited)
Bill Nagy
U.S. Policeman (uncredited)
Robert O'Neil
Reporter (uncredited)
Pat Ryan
American General (uncredited)
Stuart Saunders
Sergeant (uncredited)
Fred Stroud
Fenwickian (uncredited)
John Tatum
American Admiral (uncredited)
Mavis Villiers
Telephone Operator (uncredited)
Fred Wood
Bird Seller (uncredited)
