Local bookshops are ready to go with the release The Hallmarked Man, the eighth book in the Cormoran Strike detective series, which has been hotly anticipated in the Bailiwick ever since the Harry Potter author visited Sark last March.

Matt Jehan, who works in the Lexicon bookshop in St Peter Port, said they had 35 copies ready to go on sale but were not quite anticipating them selling like ‘hot cakes’. ‘More like warm cakes,’ he said. ‘We have only had one pre-order and that was back months ago when the release date first came out, although after the Guernsey Press article confirming the book was set in Sark, we received an order for all seven of the previous Strike novels – from someone in Sark.’

He said the shop had ordered more books than usual because of the Sark connection.

‘But the books sell well anyway and were given a boost after they were made into a TV series. Generally we keep all of the seven previous books in stock.’

Written under the pseudonym Robert Galbraith, J K Rowling has said the book was partly inspired by a 1910 novel, A Maid of the Silver Sea, by John Oxenham, also set in Sark.

‘It’s a fairly obscure book and we had not heard of it before,’ said Mr Jehan.

‘However, we have ordered two copies, which should be arriving this week.’

The shop is selling both the hardback and what is known as the trade paperback, or airside edition, which is normally found only in airport shops, and is around £10 cheaper.

‘It’s the size of the hardback, but it’s got the soft cover. They sell them in airports to keep the weight down,’ he said.

‘It’s a bit of a loophole as Guernsey is seen as one big departure lounge.’

Despite Ms Rowling visiting Sark it is not known just how much of the 900-page book is set in the island as its contents have been heavily embargoed.

‘Normally we get pre-release copies but they haven’t sent any out,’ said Mr Jehan.

‘She is such a well-known author, they know the book is going to sell anyway, even if it gets bad reviews.’