The Defector: The Untold Story of the KGB Agent Who Changed the Cold War and Saved MI5

by Richard Kerbaj

Never told in full before, this is the account of how, in 1971, the defection of a KGB agent in London led to the expulsion of more than a hundred Soviet 'diplomats' from the UK.

Drawing on newly released case files, The Defector tells a startling story of Soviet plans to plant fake double-agents within British and American intelligence services, the paranoia that ensued, and how the actions of a genuine turncoat, the former KGB agent Oleg Lyalin, and the secrets he revealed led to one of the most dramatic and pivotal moments in the Cold War.

For Lyalin's defection to Britain not only discredited a previous KGB defector, Anatoliy Golitsyn, the darling of the CIA, but eventually destroyed the reputation of the Agency's head of counterintelligence, James Jesus Angleton. As Richard Kerbaj writes: 'There was a poetic irony in Golitsyn's loss of credibility. It came, as he had previously feared, at the hands of a KGB defector. Except Oleg Lyalin had not been sent by the KGB - he was running away from it.'

At the heart of Lyalin's story is a narrative entwined with lies, disinformation, Kremlin deception campaigns, intelligence failures by the CIA and MI5, and a tangled love life. Told in full here, for the first time, by one of this country's leading commentators on intelligence and security, it shows how the Soviet Union finally lost the Cold War.

Genres: History, Espionage, Nonfiction

304 pages, Hardcover

First published September 4, 2025

Reviews

[Peter Jerram · Rating 5 out of 5]

This books brings perspective and clarity to a fascinating subject. A major addition to Cold War literature and exposes the destructive paranoia of JJ Angleton whose obsession with mythical traitors for 20 years hamstrung the battle between the democracies and the KGB. Terrific.

[Kevin Riehle · Rating 3 out of 5]

Kerbaj starts with a story about KGB defector Oleg Lyalin, who offered himself to the UK government in 1971. He then weaves into it the story of another KGB defector from a decade earlier, Anatoliy Golitsyn. Kerbaj ends up spending much more time talking about Golitsyn than about Lyalin.

Kerbaj dismantles the Angleton/Golitsyn "Master Plot" conspiracy mindset. That is a welcome contribution. However, Kerbaj takes his argument a step further by claiming that Golitsyn and Angleton might have been Soviet penetrations, rather than Yuriy Nosenko. That is a step too far. While no one did more damage to the CIA's ability to operate against the Soviet Union than Angleton and Golitsyn did, that does not mean they did it on instructions from Moscow. They were more likely psychologically unfit for their jobs, not Moscow plants.

The predominance of material about Golitsyn looks like a substitute for the lack of material available about Lyalin. Lyalin's story is probably not sufficient to fill a whole book, so Kerbaj had to overlay his story with another one.

[Andrew Macfarlane · Rating 3 out of 5]

this is an interesting time much of time. better in the last hundred pages initially I got the feeling that this was going to be more like a long newspaper article like the features in weekend American newspapers. There was a lot of irrelevant padding about the grandfather's and fathers of some of the future protagonists that in the added no great inspired context or helped the story in any way whatsoever. like with books about recent German history. even if they are about the 1980s several chapters are wasted giving a potted history of Germany since the 18th century. So here, the wartime exploits, the Tsarist actions of fathers and grandfathers gave no insight, no context and we're totally different to the actions of the majority characters themselves. they only served to pad out the book.

[Julian Walker · Rating 4 out of 5]

A great insight into the Cold War which vividly brings to life the attitudes, fashion, and style of the times which provided a backdrop to an extraordinary true life spy story.

Highly readable and absorbing, I enjoyed this immensely.