Norwich-based writer Sarah Perry saw off competition from the likes of JK Rowling and Beatrix Potter to win the Waterstones Book of the Year award with her second novel The Essex Serpent.
The Gothic novel set in the 1890s, which follows widow Cora Seaborne as she discovers her small village in Essex is being terrorised by a mythical beast, claimed an 'overwhelming' victory over five other titles, including Harry Potter and the Cursed Child and the recently discovered manuscript for The Tale of Kitty-in-Boots.
The other books nominated were all works of non-fiction by writers Emma-Jane Kirby, Christoper De Hamel and Paul Kalanithi.
Perry, whose work also includes After Me Comes the Flood, told Waterstones she was 'delighted beyond measure' to win the prestigious prize.
She said: 'From the moment The Essex Serpent was released, Waterstones' booksellers were true friends of the book, and week after week I was moved and astonished by the creativity that went into windows, displays and murals all over the country.
'No author could hope for better champions of their work, or a more heartfelt introduction to readers, and I could not be more grateful.'
Announcing the Book of the Year winner online, James Daunt, Managing Director for Waterstones revealed Perry's novel 'blazed as the overwhelming choice' by booksellers and called it a 'treasure'.
The Essex Serpent has also been nominated in the Costa Book Awards and last week was recognised by the Books Are My Bag Readers Awards as having the most beautiful cover design.
Last year's Book of the Year winner was Coralie Bickford-Smith with her debut novel The Fox and The Star.
• Have you read The Essex Serpent? Let us know what you thought of the novel in the comments below.
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