To the world’s most famous publisher of paperback books he is the spy author who has finally come in from the cold.

After 38 years with Hodder & Stoughton, John le Carré has defected to Penguin, breaking an association that brought the publisher 16 novels and the author a sizeable fortune and a second wife.

In keeping with le Carré’s fiction, the move was unexpected, enigmatic and meticulously plotted with one eye on his literary heroes Graham Greene and Joseph Conrad.

The gossipy London book world viewed the author’s partnership with Hodder, the publishing house where he met his wife, Valérie Jane Eustace, as one of the most solid and effective unions in the industry. However, at 78, the conman’s son and former spy, whose real name is David Cornwell, is more restless than all but his closest confidants realised. Last year he parted with his long-standing agent, Bruce Hunter at David Higham, and signed with Jonny Geller at Curtis Brown. Few foresaw further upheaval.

As one leading author said: “To get rid of your publisher and your agent, a writer’s two lines of defence, looks like a man clearing out the attic.”

It was unclear last night whether Geller, Penguin or le Carré was the chief architect of this latest move, which a prominent book-trade veteran described as “an extremely well kept secret”.

The advance for le Carré’s next novel is understood to be comparative with anything that he has received in the past, but money is unlikely to be the principal motivation.

Hachette, Hodder’s thriving parent company, should have been able to match any financial offer that Penguin could put together.

Robert Harris, le Carré’s official biographer, said: “I think he’s beyond caring about the money. I think what he cares about is his reputation. Penguin have that great historic track record. He sees himself in a tradition of Joseph Conrad and Graham Greene, novelists that are concerned about the big issues but also engaged with telling a gripping yarn.” Both authors are published by Penguin.

Ion Trewin, a former editorial director at Hodder, said: “David is a very hard taskmaster who expects the best from everybody all the time. At Hodder he was getting Rolls-Royce service. The idea may be that in forcing a new publisher to prove themselves he will get Rolls-Royce-plus.”

Le Carré said that the opportunity to see his work “presented by a classic paperback house with a unique backlist” was “unmissable”.

Under the terms of the new agreement, his next novel will be published by Penguin’s Viking imprint in hardback next year. At the same time two of his earlier novels, The Spy Who Came in from the Cold and The Russia House, will be reissued in Penguin Modern Classics. Over the next nine years, the rest of his backlist will transfer to Penguin as Hodder’s licences expire.

Hachette is understandably hurt to lose one of its most lucrative authors but has avoided saying so publicly.

Almost 50 years after the publication of his first novel, in 1961, le Carré seems invigorated. His last two books took him about a year each to write and, having tended to avoid publicity, he has recently granted several major interviews and last year in Hamburg he addressed an audience of 1,000 people in fluent German.

Geller, who is enjoying a purple patch of his own, after brokering the sale of international rights to Nelson Mandela’s follow up to A Long Walk to Freedom at the Frankfurt Book Fair this month said: “It’s an exciting time. I don’t think he’s ever been this productive.”

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