A true story. In the 1960s, the height of the Cold War,  the CIA recruited Greville Wynne, an insignificant British businessman doing business in Russia, to find out about Soviet plans to install missiles in Cuba. The CIA felt that Wynne would not be suspected by the KGB of doing anything  but conducting legitimate business.  Wynne makes contact with Oleg Penkovsky, a Soviet official, who feels the unbalanced Nikita Khrushchev may trigger a nuclear war between the two countries. Oleg readily feeds documents and microfilm to Wynne who, in turn, transmits them to the CIA. This information convinces the CIA that Soviet missiles were indeed placed in Cuba. President Kennedy takes action and a nuclear war was averted. Unfortunately, the KGB uncovered the spying and both Oleg and Wynne were placed in prison and tortured. Their fate subsequently rested on actions taken by their respective governments.     

Benedict Cumberbatch (Greville Wynne) / Merab Ninidze (Oleg Penkovsky) / Angus Wright (Dickie Franks, M16 Officer) / Rachel Brosnahan (Emily Donovan, CIA Officer) / Vladimir Chuprikov (Nikita Khrushchev, First Secretary, Communist Party of the Soviet Union)