The Hallmarked Man, the eighth book in the Cormoran Strike series, with the Harry Potter author writing under the pseudonym Robert Galbraith, is due out on Tuesday.
The book’s exact contents are a closely-guarded secret, but in a social media video, Ms Rowling gave her biggest hint yet that at least part of the detective’s new adventure takes part in the Bailiwick.
‘I decided that Strike and Robin were going to go to Sark,’ she said, referring to the protagonist private investigator and his partner.
‘I wanted them to go to quite a strange place, and Sark is a very unusual place. I actually loved it there.’
She also mentioned that part of the inspiration for her new book had been the book A Maid of the Silver Sea, by John Oxenham, which was published in 1910.
‘I went there [Sark] for research purposes, but it was only after I decided to send them to Sark that I became aware of this novel, which was so perfect.
‘I’ve never before in my life stumbled across something that was so perfect for epigraphs in a book, because it is the story of how they mined for silver on Sark,’ she said.
‘So it was thematically perfect, and the image of mining, particularly when you’re talking about an investigation.
‘It was just this perfect congruence, and I also really enjoyed the novel on its own terms, if anyone fancies reading it.’
The books have been drama tised in a popular BBC TV series. Filming for the seventh novel in the series, The Running Grave, published in 2023, is due to begin this autumn.
However, it remains to be seen how heavily Sark features in the book, with pre-publicity showing it centred around a dismembered corpse discovered in the vault of a silver shop in London.
The best-selling author visited Sark last March, with local businesses hoping it would lead to a boost for tourism, with fans of the series coming to see the locations featured in the book.
‘We only have a small budget to promote the island so something like this is manna from heaven,’ said Mary Nicolle, a member of Sark’s tourism committee. ‘But at this stage we do not know exactly how Sark is featured.’
She said the island had already had a boost just from Ms Rowling’s research visit.
‘The visit was very low key and her privacy was respected,’ she said.
‘But we were very grateful for her social media posts about the island, which brought a lot of interest.
‘We understand that she enjoyed being on Sark and those who met her were most grateful for her generosity in signing autographs for island residents’ children and grandchildren.
‘We hope that the publication of The Hallmarked Man will encourage more visitors to discover our beautiful island.’
Caroline Langford from Sark’s Gallery Stores said she was waiting on a shipment of the books, with readers on Sark keen to see how the island is portrayed.
‘It hasn’t arrived yet, so we will be chasing it up today, she has quite a few fans over here,’ she said.
‘I’ll definitely be reading it myself. I love her books, and we are really excited to see what happens in Sark.’