Smileys People

by John le Carre

George Smiley is called out of retirement when one of his former assets, an émigré general, is found murdered. In tidying up loose ends for the "Circus", his former employer, he discovers a clandestine operation run by his nemesis, Karla, for his own personal benefit. Smiley is able to use this irregularity against Karla, forcing him to defect to the West.