Cliff Robertson as David Frazer

Jack Hawkins as Colonel Drexel

Marisa Mell as Sophie

Michel Piccoli as Georges Sarrassin

Bill Fraser as Leslie Dunwoody

Charles Gray as Benson

John Le Mesurier as Sir Robert

Felix Aylmer as Henrickson

Christopher Witty as Prince Jamil

Tutte Lemkow as Paviot

Ernest Clark as Minister

Keith Pyott as Gustave

Jose Burgos as El Mono

James Payne as Russian Officer in Tent (uncredited)

Jerold Wells as Brindle (uncredited)

George Roderick as Officer at Circus (uncredited)