John le Carre has written his first novel in more than 25 years to feature fictional spy George Smiley.
The Night Manager author's most famous character, who features in The Spy Who Came in from the Cold and Tinker Tailor Soldier Spy, will return in September.
A Legacy of Spies tells the story of Smiley's colleague Peter Guillam, whose Cold War past catches up with him.
Publishers Viking Books said it was "as ingenious and thrilling" as the previous Smiley books.
It blends past and present as Guillam is called back to London from his retirement in Brittany.
Explaining the plot - and the involvement of Smiley - Viking Books said: "Intelligence operations that were once the toast of secret London, and involved such characters as Alec Leamas, Jim Prideaux, George Smiley and Peter Guillam himself, are to be scrutinised under disturbing criteria by a generation with no memory of the Cold War and no patience with its justifications."
The spy is also featured in books including Smiley's People and Le Carre's first novel Call for the Dead, and his exploits have been portrayed on the big and small screen.
Alec Guinness played him in two television adaptations in 1979 and 1980, while more recently, Gary Oldman took on the role in a film version of Tinker Tailor Soldier Spy in 2011.
But it is the BBC adaptation of le Carre's 1993 work The Night Manager - which doesn't feature the famous spy - that has been the author's most prominent recently, winning three of its stars Golden Globes earlier this year.
The same team behind the show, starring Tom Hiddleston and Olivia Colman, are to make a new version of The Spy Who Came in from the Cold, which will appear on BBC One next year.