Tinker tailor soldier spy

Many British intelligence officers guessed that a "mole" working for the USSR had long been in its leadership. But for some reason, those who dared to declare this openly ended up in retirement. The others preferred to keep quiet. But the confirmation of the Russian agent's existence came from a completely unexpected direction. An undercover investigation begins, led by retired George Smiley. And no one, including the top intelligence leadership, should guess that the mole is being hunted again.