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.
On the vacation of a lifetime in Egypt, an elderly French couple are brutally murdered. Days later, a meticulously-planned kidnapping takes place on the streets of Paris. Amelia Levene, the first female Chief of MI6, has disappeared without a trace, six weeks before she is due to take over as the most influential spy in Europe. It is the gravest crisis MI6 has faced in more than a decade. Desperate not only to find her, but to keep her disappearance a secret, Britain's top intelligence agents turn to one of their own: disgraced MI6 officer Thomas Kell. Tossed out of the Service only months before, Kell is given one final chance to redeem himself - find Amelia Levene at any cost. The trail leads Kell to France and Tunisia, where he uncovers a shocking secret and a conspiracy that could have unimaginable repercussions for Britain and its allies. Only Kell stands in the way of personal and political catastrophe.
Thomas Kell thought he was done with spying. A former MI6 officer, he devoted his life to the Service, but it has left him with nothing but grief and a simmering anger against the Kremlin.
Then Kell is offered an unexpected chance at revenge. Taking the law into his own hands, he embarks on a mission to recruit a top Russian spy who is in possession of a terrifying secret. As Kell tracks his man from Moscow to London, he finds himself in a high stakes game of cat and mouse in which it becomes increasingly difficult to know who is playing whom.
As the mission reaches boiling point, the threat of a catastrophic terrorist attack looms over Britain. Kell is faced with an impossible choice. Loyalty to MI6—or to his own conscience?