Tinker Tailor Soldier Spy is a 1974 spy novel by British-Irish author John le Carré. It follows the endeavours of taciturn, aging spymaster George Smiley to uncover a Soviet mole in the British Secret Intelligence Service. The novel has received critical acclaim for its complex social commentary—and, at the time, relevance, following the defection of Kim Philby. It has been adapted into both a television series and a film, and remains a staple of the spy fiction genre.

David John Moore Cornwell, better known by his pen name John le Carré, was a British author, best known for his espionage novels, many of which were successfully adapted for film or television. A "sophisticated, morally ambiguous writer", he is considered one of the greatest novelists of the postwar era. During the 1950s and 1960s, he worked for both the Security Service (MI5) and the Secret Intelligence Service (MI6). Near the end of his life, due to his strong disapproval of Brexit, he took out Irish citizenship, which was possible due to his having an Irish grandparent.