Somerset-born author's new novel inspired by a true story

Jason Mann, who was born in Bishop’s Hull, near Taunton, and writes as J.H. Mann, began work on House of Twisted Shadows after learning about Knowstone Manor.

The manor, located on the edge of Exmoor and built in 1934 for a wealthy German bachelor, featured unusual architecture, a glass dome, and a rumoured secret passageway.

Mr Mann said: "It was one of the most remarkable true stories I have ever encountered.

"To describe it as stranger than fiction is no exaggeration."

Mr Mann, now based in Torquay, was particularly fascinated by rumours that the manor was used to signal enemy aircraft during the Second World War.

Aerial photos allegedly showed the building’s layout resembled a swastika.

He said: "I knew immediately that I had found the setting for what would become my fourth novel, House of Twisted Shadows.

"As a journalist, I have always been fascinated by stories that leave unanswered questions, and Knowstone Manor was exactly that."

Set during the harsh winter of 1962, House of Twisted Shadows follows Amelia Tremayne as she returns to a remote clifftop house to investigate the mysterious death of her father a decade earlier.

Although inspired by Knowstone Manor, Mr Mann relocated the story to Cornwall's dramatic Atlantic coast to heighten the isolation and suspense.

He said: "Every new piece of research uncovered another mystery, and I soon found myself imagining what might have happened if some of the rumours surrounding the house were true."

Jason Mann has already seen success with his previous work.

His novel The Silver Tide, which tells the story of a fisherman’s daughter who helps found her village’s first lifeboat crew after losing her family in a summer storm, won the 2026 Holyer an Gof General Fiction Award.

Judges praised the novel’s storytelling, meticulous research and vivid evocation of a 19th-century fishing community.

Knowstone Manor was almost destroyed by fire in the 1960s.

One of the few objects reportedly recovered from the site was a spoon engraved with a swastika.

Mr Mann is also a shore-based volunteer for the RNLI at Teignmouth.

House of Twisted Shadows is available now as a paperback or Kindle ebook from Amazon and other major retailers.

The book’s cover was designed by Ukrainian firm MiblArt, based in Lviv.

Mr Mann’s other novels include Hidden Depths and The Echoing Shore.

Copies of House of Twisted Shadows are available through Amazon and other major retailers.