Vlassov is a Soviet spy who defects in France. He is whisked to the U.S, where Allan Davies takes over the case. After polygraph tests and cross-examinations, Vlassov names several Western European agents who are also spying for the Soviets. Davies wants to take the listed agents into custody; meanwhile, those on the list start dying under mysterious circumstances.
Yul Brynner
Henry Fonda
Dirk Bogarde
Virna Lisi
Robert Alda
Farley Granger
Philippe Noiret
Michel Bouquet
Martin Held
Guy Tréjan
Marie Dubois
Elga Andersen
André Falcon
William Sabatier
François Maistre
Paola Pitagora
Herbert Fux
Eva Maria Meineke
Luigi Diberti
Robert Party
Nathalie Nerval
Jean Desailly