Last fall, J.K. Rowling's first novel written for an adult audience, The Casual Vacancy, was released to much hype. Naturally, it was an instant best-seller, but reviews were mixed. By contrast, new novelist Robert Galbraith's detective novel The Cuckoo's Calling, was released with little awareness and rave reviews. What does one of the best-selling authors of all time have to do with a first time writer and former MP investigator? Turns out, she is him.

The Sunday Times of London has discovered that J.K. can now join the ranks of successful authors who have turned to pseudonyms to write freely and away sans deafening anticipation. Rowling told the Sunday Times: "“I had hoped to keep this secret a little longer, because being Robert Galbraith has been such a liberating experience. It has been wonderful to publish without hype or expectation, and pure pleasure to get feedback under a different name.”

The Cuckoo's Calling follows soldier-turned-private investigator Cormoran Strike, investigating the suicide of a famous super-model. In other words, it's classic, hard-boiled noir stuff, and the last thing you'd expect from the Harry Potter mastermind. According to the reviews, she nailed it. Now that the secret's out, the book has already skyrocketed to #1 on Amazon best-seller lists in Britain as well as the states.

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[via NYT]