the main character's best friend betrays his country

George Smiley, the aging master spy of the Cold War and once heir apparent to Control, is brought back out of retirement to flush out a top level mole within the Circus. Smiley must travel back through his life and murky workings of the Circus to unravel the net spun by his nemesis Karla 'The Sandman' of the KGB and reveal the identity of the mole before he disappears.

In the bleak days of the Cold War, espionage veteran George Smiley is forced from semi-retirement to uncover a Soviet mole within his former colleagues at the heart of MI6.

Years after his squad was ambushed during the Gulf War, Major Ben Marco finds himself having terrible nightmares. He begins to doubt that his fellow squad-mate Sergeant Raymond Shaw, now a vice-presidential candidate, is the hero he remembers him being. As Marco's doubts deepen, Shaw's political power grows, and, when Marco finds a mysterious implant embedded in his back, the memory of what really happened begins to return.

Near the end of the Korean War, a platoon of U.S. soldiers is captured by communists and brainwashed. Following the war, the platoon is returned home, and Sergeant Raymond Shaw is lauded as a hero by the rest of his platoon. However, the platoon commander, Captain Bennett Marco, finds himself plagued by strange nightmares and soon races to uncover a terrible plot.

Western journalists visit Moscow to interview Adrian Harris, a former controller in British intelligence who was also a double agent for the USSR. Harris believes in both Communism and Englishness, believing himself to have betrayed his class, but not his country. The press find these beliefs incompatible, and want to find out why he became a ‘traitor’. Harris is plagued by anxieties over both his actions and his upper-class childhood, and drinks to a state of collapse