When it was revealed that the detective thriller, The Cuckoo's Calling, was written by Potter series author JK Rowling, the sales hit the roof. In US, before the revelation only 500 copies of the book were sold and now the publisher has order 300,000 copies for the US.
Now the second mystery of who leaked the real identity of Robert Galbraith is out in the open.
A law firm representing the Harry Potter creator is the source of the leak. Like a detective novel, it emerges that even the firm is not the primary source of information.
A Twitter post by a woman called Judith Callegari had blown the lid on publishing's best kept secret and alerting a Sunday newspaper.
And Judith Callegari is the best friend of the wife of senior lawyer Chris Gossage, a partner in Russells law firm.
Gossage has said that he mentioned about the real identify of Robert Galbraith in a "private conversation" to someone he said he "trusted implicitly".
Rowling has said she was "disappointed" and "angry" that a partner at entertainment firm Russell's had told his wife's best friend the real identity of Robert Galbraith, the pseudonym she had used for the publication The Cuckoo's Calling.
In a statement Rowling said she felt betrayed. "I have today discovered how the leak about Robert's true identity occurred. 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," she said yesterday.
"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," she has said.
The law firm Russells said it had contacted Rowling's agent as soon as the newspaper story came out: "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. Whilst accepting his own culpability, the disclosure was made in confidence to someone he trusted implicitly."
It added: "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 detective novel was rejected by a number of big publishers.