In theory, this is the same intelligence service (MI6 Cirque) than James Bond. But instead of glamor, fast cars and elaborate shootings, this is the laborious paperwork, the routine of against-examination by former officers tired, and finally a morally ambiguous unmasked traitor.
The real past of the author in the intelligence infuses everything with a convincing realism. Jargon and full explanation of any practice that is absence that brings with them a feeling of true immersion into the world of espionage trouble and almost shabby. Also this novel takes us into a dark England, gray, cold and depressing 70s, in almost another world. Finally, through the mission of George Smiley, this is a whole section of contemporary history, the Cold War, which is told us.
This story plays out in a general context of treason treason against the state of the mole British betrayal of agents managed by the mole, linfidélité woman Smiley, and more general betrayal of lidéalisme almost unmarked by the leaders of Cirque Quà who think their personal interest.
Do not let anyone spoil your fun to find out who the mole and do not be put off by secondary intrigue, apparently unrelated, the teacher of the school.
This is primarily an incredibly fascinating story that will keep you spellbound from start to finish.
