What if... Harold Wilson had been a spy

“It was all a misunderstanding," Mary Wilson says quietly, her hands cradling a cup of tea. "Harold never meant to let anybody down."

Her eyes travel across the signed photographs of John Betjeman and Harry Secombe, souvenirs of a country to which she can never return. Beside her on the battered sofa, her flatmate pours another glass of vodka. "We love it here, honestly," says Marcia Williams, fiddling absent-mindedly with her chipped Hero of the Soviet Union medal. "It can get a bit cold in the winter. But when you've grown up in Northampton, you can handle anything."

Now that MI5's official history has confirmed the allegations, you wonder how anyone could ever have doubted that Harold Wilson was a Soviet agent. Amazingly, the intelligence officer who first uncovered the story, Peter Wright, was dismissed as a paranoid fantasist. Now we know that Wright was the only sane man in the asylum: from the late 1940s onwards, Wilson was in the pay of the KGB. Whether he did it for ideological reasons, or simply for money, we will probably never know.

But why did nobody see the signs? During the 1960s, Wilson's economic policy, which included the humiliating devaluation of the pound, seemed almost deliberately self-defeating. The explanation, it emerges, was that he was following the advice of a defunct Soviet textbook, which might have worked in an economy based on tractors, but was supremely ill-suited to bringing the "white heat" that Wilson had promised.

He holidayed on the Scilly Isles, not because he liked them, but because he could take instructions from a Russian sub lurking offshore. He smoked a pipe because he could leave messages for his handlers in the patterns of the ash. He even wore his trademark Gannex raincoats for subversive reasons. Journalists thought he was trying to look modern; in fact, he was walking around with reams of microfilm sewn from collar to knee.

It all went wrong for Wilson, though, when he got back into power in March 1974. With the economy heading downhill and Wright closing in, he decided to make a break for safety. On 20 August 1974, he vanished entirely, leaving only a pile of abandoned clothes on a Scilly Isles beach.
The press immediately assumed he had decided to end it all, and so the shock was all the greater when he resurfaced in the Siberian city of Krasnoyarsk.

Biographers have suggested he might have expected a rather better welcome from Leonid Brezhnev. But Mary Wilson and Marcia Williams, who faithfully followed him east a few years later, see things differently. "It's lovely here, really," Mary says. "Harold always said it reminded him of Huddersfield."