Academy Award® winner Errol Morris pulls back the curtain on the storied life and career of David Cornwell, the former spy known to the literary world as John le Carré.
Harry Palmer heads a private investigation business based in Moscow. His associates are Nikolai "Nick" Petrov (Jason Connery), ex-CIA agent Craig (Michael Sarrazin), and ex-KGB Colonel Gradsky (Lev Prygunov). They take on the job of finding 1000 grams of weapons-grade plutonium stolen from the Russian government, though they do not know the identity of their client.
Set in the 1970s, Tinker, Tailor, Soldier, Spy finds George Smiley, a recently retired MI6 agent, doing his best to adjust to a life outside the secret service. However, when a disgraced agent reappears with information concerning a mole at the heart of the Circus, Smiley is drawn back into the murky field of espionage.
Tasked with investigating which of his trusted former colleagues has chosen to betray him and their country, Smiley narrows his search to four suspects—all experienced, urbane, successful agents—but past histories, rivalries and friendships make it far from easy to pinpoint the man who is eating away at the heart of the British establishment.