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ordering. Hello and welcome to the History Extra podcast from BBC History magazine,

Britain's bestselling history magazine. I'm Ellie Corthon. In today's episode, you'll be hearing

from Trevor Barnes, a writer and historian of espionage whose latest book Dead Doubles explores

a fascinating counter espionage investigation by MI5 to uncover the infamous Portland spying.

One of the most dangerous KGB espionage rings ever to operate in the UK. The revelation of these

deep-cover Russian agents shocked the West in the early 1960s and it's an operation that continues

to resonate today. Putting the questions to Trevor was our acting digital editor, Ellen Revens.

So your book Dead Doubles explores the remarkable counter espionage operation by MI5 that uncovered

the Portland spying in the very early 1960s. It's obviously a very famous espionage case of the

Cold War, particularly at the time. But for listeners who might not be asked familiar with this case,

could you give us an introduction on how you came to write about it? Well, I came to write about it

because having changed careers a few times, I wanted to start writing non-fiction. I had written

and published three thriller, Police Procedureals with a Female Detective and I'd always been

interested in spying as a history issue. I studied it when I was at university and had

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