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The Defector

The untold story of the KGB agent who saved MI5 and changed the Cold War - 'Reads like le Carré', Robert Verkaik

Richard Kerbaj author

Format:Hardback

Publisher:John Blake Publishing Ltd

Published:4th Sep '25

Should be back in stock very soon

The Defector cover

The first full account of the defection of the KGB agent Oleg Lyalin in 1971, which rescued MI5 after a series of disastrous intelligence failures

The first full acount of the defection of the KGB agent Oleg Lyalin in 1971, which rescued MI5 after a series of disastrous intelligence failures

'Beautiful. It looks and reads like a novel . . . all queuing up to lavish praise upon [this] book." James O'Brien

'An absolutely thrilling read based on deep research which brings this MI5 asset's importance to life.' Gordon Corera, co-host of The Rest is Classified

'Kerbaj is well-placed to recount the facts of this forgotten story . . . one of the most sensational episodes of the Cold War.' Sunday Times

'A truly gripping, untold story... The Defector reads like Le Carre but uncovers important truths that are being played out in Putin's Russia today'. Robert Verkaik

'Extraordinary' - Hugo Rifkind, TimesRadio

'Inspired . . . seamless, and a thrill to read.' The Scotsman

'Compelling', Evening Standard

'Highly entertaining . . . Certainly the stuff of thrillers.' Sydney Morning Herald

'This magnificent book reads like a thriller but it's all true. It has big lessons for today and tomorrow.' The Australian

'Reads like a spy novel', Express

The Defector is the untold account of how, in 1971, the defection of a KGB saboteur in London led to the expulsion of more than a hundred Soviet 'diplomats' from the UK.

Drawing on newly declassified intelligence documents and dozens of interviews with spymasters, The Defector tells a startling story of a Soviet mission to plant fake Kremlin agents within British and American intelligence services, the paranoia that ensued, and how the actions of a genuine turncoat, the former KGB officer Oleg Lyalin, and the secrets he revealed resulted to one of the most dramatic and pivotal moments in the Cold War.

Lyalin led MI5 to rethink its relationship with the CIA. And his defection discredited a previous KGB defector, Anatoly Golitsyn, the darling of the CIA, and ultimately destroyed the reputation of the US 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...

'An absolutely thrilling read based on deep research which brings this MI5 asset's importance to life' -- Gordon Corera, co-host of The Rest is Classified
Kerbaj is well-placed to recount the facts of this forgotten story . . . one of the most sensational episodes of the Cold War. * Sunday Times *
An explosive book about the extraordinary life of Oleg Lyalin * Mail on Sunday *
'A truly gripping, untold story of how a Russian defector helped British intelligence defeat the Soviet spies. Richard Kerbaj's painstaking research, including interviews with key players, upends much of the orthodoxy about what happened in the Cold War. The Defector reads like Le Carre but uncovers important truths that are being played out in Putin's Russia today' -- Robert Verkaik, Sunday Times Bestselling author of The Traitor of Colditz
'A lucidly written account of a significant setback for Soviet intelligence. Dynamic and vivid, reads like a spy thriller. Kerbaj skillfully makes major figures of the Cold War cloak-and-dagger operations come to life: defectors Oleg Lyalin and Anatoly Golitsyn, CIA counterintelligence chief James Angleton, MI5 director Martin Furnival Jones, KGB chairman Yuri Andropov, and many others' -- Dr. Filip Kovacevic, University of San Francisco and author of KGB Literati: Spy Fiction and State Security in the Soviet Union

ISBN: 9781789468489

Dimensions: 243mm x 164mm x 32mm

Weight: 574g

304 pages