How J.K. Rowling's 'Cuckoo's Calling' Charade Unraveled

A lawyer tells his wife, the wife tells her friend, the friend tells the press -- and a well-kept secret is out of the bag.

Loose lips sink ships -- and they also spoil literary secrets.

The source of a tip that led to the unmasking of Robert Galbraith, author of murder mystery The Cuckoo's Calling, as none other than Harry Potter creator J.K. Rowling has been revealed.

The surprising news was reported over the weekend by the Sunday Times, which was tipped off by a tweet from account @JudeCallegari, which quickly was deleted, and the well-received book swiftly shot up to the top of the best-seller charts.

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That tipster first was revealed by The Standard to be Judith Callegari, a mother of two from Surrey, England. Callegari's husband, Paul Callegari, is a partner at the law firm K&L Gates.

But how did Callegari learn of the truth behind Robert Galbraith, billed on the dust jacket as a former member of the Royal Military Police "who was later attached to the SIB (Special Investigative Branch)?" 

The answer: Her best friend is a woman married to Chris Gossage, a partner at another firm, Russells Solicitors, that reps Rowling. 

The revelation has resulted in a statement of apology from the firm to its billionaire author client.

"We, Russells Solicitors, apologise unreservedly for the disclosure caused by one of our partners, Chris Gossage, in revealing to his wife's best friend, Judith Callegari, during a private conversation that the true identity of Robert Galbraith was in fact JK Rowling," it reads.

"Whilst accepting his own culpability, the disclosure was made in confidence to someone he trusted implicitly. On becoming aware of the circumstances, we immediately notified JK Rowling's agent. We can confirm that this leak was not part of any marketing plan and that neither JK Rowling, her agent nor publishers were in any way involved," the statement continues.

Rowling has issued a statement of her own, expressing her profound disappointment over the divulging of the well-kept secret.

"I have today discovered how the leak about Robert's true identity occurred," she said Thursday. "A tiny number of people knew my pseudonym, and it has not been pleasant to wonder for days how a woman whom I had never heard of prior to Sunday night could have found out something that many of my oldest friends did not know."

"To say that I am disappointed is an understatement. I had assumed that I could expect total confidentiality from Russells, a reputable professional firm, and I feel very angry that my trust turned out to be misplaced."

The book, about a war vet-turned-private eye, is published by Sphere, an imprint of Little, Brown, which published Rowling's last book, The Casual Vacancy.