Harry Potter author K Rowling has been revealed as the author of The Cuckoo’s Calling, a crime novel published in April of this year under the name Robert Galbraith.

The book, which was a critical success following its release, tells the story of the mysterious death of a model, who falls from a balcony, and the private investigator and former war veteran who is on the case.

Dubbed a “stellar debut” when critics believed it was penned by Galbraith, Rowling told The Sunday Times she would like to have stayed hidden for longer as the true author.

She said;  “Being Robert Galbraith has been such a liberating experience… It has been wonderful to publish without hype and expectation and pure pleasure to get feedback under a different name.”

She may be protesting too loudly though, the New Statesman reports that since the news broke last night that the novel came form Rowling’s pen, sales have increased 150,000 per cent in less than 24 hours.

Rowling published her first novel for adults, The Casual Vacancy, last year, to mixed reaction. That novel is now set for a forthcoming BBC adaptation.