J.K. Rowling has been revealed as the secret author of crime novel "The Cuckoo's Calling," London's Sunday Times discovered this weekend.
The "Harry Potter" scribe wrote the story about a war veteran-turned-private investigator under the pseudonym Robert Galbraith.
"It has been wonderful to publish without hype or expectation, and pure pleasure to get feedback under a different name," she said in a statement.
"Cuckoo's Calling" had sold 1,500 copies before the secret was revealed. Within hours, sales rose to more than 5,000 places to the top of Amazon's sales list.
The book received glowing reviews before Rowling's identity as the true author was exposed.
One critic described the book as a "scintillating debut," while Val Mcermid in the Guardian called it "the best of traditional mystery fiction, private-eye pace and the kind of writing that reminds me why I love this genre."
It was suspected that Rowling was writing a crime novel when it was announced that the editor of her first adult book would be David Shelley, who comes from a background of crime and thriller writing.
The fact that Rowling and "Galbraith" had the same agent and editor was one clue that she might be the true author, especially since the novel's text didn't sound like the voice of a first-time novelist. The Sunday Times began to investigate after receiving an anonymous tip via Twitter.
Rowling had said in interviews that the idea of writing under a nom de plume, post "Potter," was appealing.
"The Cuckoo's Calling" was published by Sphere, part of Little Brown Book Group, which also published Rowling's first effort into adult tomes, "The Casual Vacancy."
Another Cormoran Strike book is set to be published next year.