The Serpent (1973)

The Serpent
Thriller
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.
Starring
Yul Brynner, Henry Fonda, Dirk Bogarde, Virna Lisi, Robert Alda, Farley Granger, Philippe Noiret, Michel Bouquet, Martin Held, Guy Tréjan
Directed By
Henri Verneuil