JK Rowling's publishers have reprinted 140,000 copies of her crime debut to meet demand after it emerged she had secretly written the novel under a false name.
The Harry Potter author was outed as the writer of The Cuckoo's Calling at the weekend, having published the book as Robert Galbraith.
But since it was revealed she was behind the book sales have rocketed, bookshops have sold out and the hardback has gone to the top of the Amazon bestseller chart.
Despite the book being written under a different name, the novel - about a war veteran turned private investigator called Cormoran Strike - was praised by reviewers, although it had shifted just 1,500 copies since it came out in April.
She was rumbled after The Sunday Times looked into how a first-time novelist could produce such an assured debut work.
After being exposed she said: "I 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 from publishers and readers under a different name."
The book was published by Sphere, part of Little, Brown, which published her last novel, The Casual Vacancy.
Rowling has now indicated she will write further books in the series.
"To those who have asked for a sequel, Robert fully intends to keep writing the series, although he will probably continue to turn down personal appearances," she said.
A spokesman for Waterstones said: "Ever since the news broke we've had countless people coming in asking for a copy: the few we had left of the original release flew off the shelves. We expect copies to begin arriving in Waterstones tomorrow.
"It's a gift for bookshops and readers - for bookshops because major new releases don't usually come out in the middle of the year, and for readers because this is surely a perfect summer book. Although JK Rowling fans have had time to download a digital copy, we know from experience they like to have the physical book and the first place they will be able to pick one up tomorrow will be a proper, bricks and mortar bookshop - no need to wait for the post."
A spokesman for printing firm Clays said: "We were astonished to read on Sunday about J K Rowling's decision to publish her crime novel under a pseudonym. We have been surprised by overnight successes in the past, but never to this extent.
"Monday was spent sourcing materials and gearing the factory up to get books into production as fast as possible, and distribution plans in place. We started printing late on Monday evening - with no warning and no material, this was no mean feat.
"We have produced all of J K Rowling's books at Clays so we were delighted and proud to find we had done this one. First copies are off press and being dispatched. We have produced prize-winning reprints in the past, but there is at least a skeleton plan for those, this time there was none, which has made it a tense but very exciting 72 hours."