The Courier is a true-life spy thriller, the story of an unassuming British businessman Greville Wynne (Benedict Cumberbatch) recruited into one of the greatest international conflicts in history. At the behest of the UK's MI-6 and a CIA operative (Rachel Brosnahan), he forms a covert, dangerous partnership with Soviet officer Oleg Penkovsky (Merab Ninidze) in an effort to provide crucial intelligence needed to prevent a nuclear confrontation and defuse the Cuban Missile Crisis.