* Melina Mercouri as Elizabeth Lipp
* Maximilian Schell as Walter Harper
* Peter Ustinov as Arthur Simon Simpson
* Robert Morley as Cedric Page
* Jess Hahn as Giulio
* Akim Tamiroff as Harback
* Titos Vandis as Yusuf
* Georges Savalas as Gerven
* Desmond Llewelyn as British Agent
* John Le Mesurier as British Agent
* Nadja Regin as Guilia
* Johanna von Koczian as Ilham