It's easy to see why Jk Rowling wanted to publish a book under another name. After her first post-Potter adult novel A Casual Vacancy was released, every aspect of the writing was torn apart by critics and the media; her writing crushed under the weight of expectation and comparison. 

JK Rowling
Rowling Probably Didn't Want Her Adult Fiction Compared To Harry Potter.

Sure, Harry Potter made her a mega-millionaire but the author didn't want to put away her typewriter and lounge around in piles of cash, she wanted to write more, for completely different audiences. So Rowling assumed the guise of Robert Galbraith, a first-time author "with a background in the army and the civilian security industry" and enlisted the help of her editor, David Kelly, who she now describes as a "true partner in crime" to get crime novel The Cuckoo's Calling into print.

The novel - about an ex-army private investigator who is called upon to solve the death of a model - was extremely well received by critics, readers and other crime others alike. Crime writer Peter James uploaded a review of "Galbraith's" novel on Amazon, saying "Everytime I put this book down, I looked forward to reading more. Gabraith writes at a gentle pace, the pages rich with description and with characters that leap out of them. I loved it. He is a major new talent."

JK Rowling
Rowling Certainly Fooled Everyone...Even If It Was Only For A Little While.

Professor Peter Millican of Hertford College at the University of Oxford has stepped forward as responsible for Rowling's unmasking, sparking a surge in sales on bookseller Amazon's website of 507,000%. Speaking to the BBC, the expert in computer linguistics who had developed software to analyse and compare texts to see if there were any similarities between the Galbraith novel and Ruth Rendell, Val McDermid, JK Rowling and PD James, as requested by The Sunday Times who had launched an investigation to find out how a first-time writer could be so self-assured and critically successful.

Val McDermid
Crime Writer Val McDermid Was Suspected To Have Written The Cuckoo's Calling.

"I was testing things like word length, sentence length, paragraph length, frequency of particular words and the pattern of punctuation," explained Prof Millican, "What was striking about the tests was how often The Cuckoo's Calling came closest to the texts by JK Rowling and it was closer to those than to any other crime novels. In the vast majority of these tests I found that the new book came closer to A Casual Vacancy and/or Harry Potter and the Deathly Hallows than it came to the other six books by the other three authors. The analysis corroborated quite strongly the hypothesis that had been put to me that she had written [The Cuckoo's Calling].

JK Rowling
She'll Have To Think Of A New Way To Fox Those Clever Oxford Proffessors!

The book also raised suspicion when readers noticed how well a man - and an ex-army guy at that - described women's clothes. Describing the experiment as "liberating," the sneaky author herself said "It has been wonderful to publish without hype or expectation, and pure pleasure to get feedback under a different name.''