Ben Macintyre tells the fascinating true story of the only woman to become a top Soviet spy

Mrs. Len Beurton of Great Rollright, a tiny village in the Cotswolds, was an apparently ordinary housewife and mother of three, famous for her home-baked scones.

In reality, she was Agent Sonya, a top Soviet operative, transmitting plans for the atomic bomb from an outhouse in her Oxfordshire garden. Her real name was Ursula Kuczynski and her intelligence work took her from her native Germany to Shanghai, Japanese-occupied Manchuria, Poland, Switzerland and England.  

Ursula's eventful life is the subject of Ben Macintyre's compelling new book, Agent Sonya: Moscow's Most Daring Wartime Spy. The British journalist is known for his bestselling accounts of international espionage — stories of intrigue, romance, betrayal, war, loyalty and conflicted morality. Over the past 30 years, he's produced a dozen engaging, authoritative studies of high-profile figures ranging from Britain's famed double agent Kim Philby to Moscow's Oleg Gordievsky, who spied for Britain. He is also currently a columnist and associate editor for the Times U.K.

Macintyre spoke to Eleanor from his home in London.

Of skullduggery and deception

"This probably reflects very badly on me, but I am fascinated by these terrible characters who live double lives and lives of skullduggery and deception.  

"In my case, it started very early on. Before I even left school at the University of Cambridge, I was approached by one of my teachers who asked me if I'd meet somebody from the Foreign Office who is not part of the 'regulation' Foreign Office — which was completely obvious code for 'Would you like to be interviewed by MI:6?'

"I was interested, but they worked out pretty quickly that I was not the right material for a spy, because I find it quite hard to keep a secret.

This probably reflects very badly on me, but I am fascinated by these terrible characters who live double lives and lives of skullduggery and deception.

"But it left me with a long fascination with spies. I think spies are a wonderful background to write about because you can invade the territory that is normally occupied by novelists: loyalty, love, deception, betrayal, romance, adventure. 

"And yet, if you have the right depth of material, it's all true. And so you can write something that feels like a novel, but is nonetheless absolutely true."

Her name was Ursula

"Ursula's story lurks, as it were, in the background of a lot of other spy stories. She appears as this rather shadowy figure. Partly because she was a woman, she has never really been treated with the same respect that would be accorded to her had she been a man. 

"And in fact, she was quite the equal and a far better spy than many of those that I've written about in the past and that others have written about. 

Partly because she was a woman, she has never really been treated with the same respect that would be accorded to her had she been a man.

"But I came across her first because I was actually researching a completely different story, the story of an American intelligence operation at the end of the Second World War, when the Americans in Britain were recruiting emigre Germans, people who had fled from the Nazi regime, who would be prepared to parachute into the dying chaos of the Reich and spy in the last bits of it — the 'Good Germans,' as it were. 

"But what they didn't know was that all of these supposedly Good Germans were, in fact, communists that were being put up for recruitment by Ursula. 

"That was the first time I'd ever really got to grips with who she really was. And then I backtracked on the story, and I found this incredible tale that took us from Shanghai to China, to Japanese-occupied Manchuria, to Switzerland, to Poland — and then finally to Britain. And it's a much bigger story than the one I thought I was picking up."

Where her loyalties lay

"Ursula came from a bourgeois Jewish intellectual academic family. Her parents were really quite well off. They lived in a rather exclusive suburb of Berlin. 

"Ursula grew up between the wars during the Weimar Republic, that extraordinary chaotic period in German history which was both economically disastrous, but also intellectually and culturally fascinating. 

She was a fully dedicated communist. That makes her, to me, terribly interesting.

"She witnessed the rise of Nazis and, like many of her ilk on the left, she believed that only communism was going to oppose the rise of Hitler. And she became a communist; she joined the party at the age of 17 and never left it. 

"She was a fully dedicated communist. That makes her, to me, terribly interesting. From our perspective, we look back at her through the prism of the Cold War. 

"But to us today, communism is a simple, unalloyed evil."

The unassuming 'Mrs. Beurton'

"It seems like a strange thing to say, but in a way, Ursula's greatest disguise, her best camouflage, was her gender. 

"The fact that she was a woman made her invisible to successive people who were out for her blood, even those who really suspected her. So she was hunted over the years, not just by the Chinese secret police, but by the Japanese Kempeitai, a terrifying kind of Gestapo-like secret police, the Gestapo itself, MI5, MI6 and the Polish secret police. 

"In fact, there are these extraordinary memos in the British archives of the British Security Service, saying, and I'm not exaggerating here, 'Well, we're investigating, but it can't be Ursula (or Mrs. Beurton as she was then known) because she has three children and she bakes particularly good cakes.' 

The fact that she was a woman made her invisible to successive people who were out for her blood, even those that really suspected her.

"They literally could not see her, because she was a woman. She knew that, and she ruthlessly exploited it. So in a way, that was her greatest defence.

"But she did have a love of danger, there's no doubt about that." 

Ben Macintyre's comments have been edited for length and clarity.