Thomas Kell is a disgraced agent who longs to come in from the cold. When MI6’s top spy in Turkey is killed in a mysterious plane crash, his chance arrives… for Kell is the only man Service Chief Amelia Levene can trust to investigate the accident.

In Istanbul, Kell soon discovers that there is a traitor inside Western Intelligence. Then he meets Rachel- the dead spy’s daughter- and the stakes grow higher still.

From London to Greece and into Eastern Europe, Kell tracks the mole. But a betrayal close to home transforms the operation into something more personal. Soon Kell will stop at nothing to see it through.