Author Oliver Harris talks to Imogen Blake about the third instalment in his Hampstead detective series, which finds Nick Belsey suspended from his job and squatting in the closed-down police station when he falls into the seemingly glitzy world of celebrity.

The closure of Hampstead police station in 2013 sent ripples of anger through the community, which are still being felt today. Residents believe it has contributed to a rise in violent crime, and are now raising money to ‘buy in’ extra police officers for the area.

For Hampstead-born author Oliver Harris, it posed a different problem: what would become of his cynical fictional detective Nick Belsey, who is based at Hampstead CID?

There’s no mention of Hampstead’s crowdfunding campaign for more police officers – “I think Belsey would be profoundly disdainful of the idea,” quips Harris – but the closure of the police station forms the jumping off point for the third novel in the Belsey series, The House of Fame.

“After the police station closed, I had people saying to me, ‘what’s going to happen to Belsey?’” says Harris, who has lived in Kentish Town and Hampstead but now resides in Finsbury Park.

“There was part of me that thought, oh it doesn’t matter, it’s just fiction, but part of me said, ‘hang on, that might be great.’ Actually the Ham&High ran a brilliant piece on what it was like inside the station with photos, and I just thought: now that is a location.”

The novel begins with Belsey squatting his former place of work, when his new life is suddenly interrupted by a knock at the door of the otherwise-abandoned Hampstead police station, by an elderly woman with dementia who is looking for her son.

Escorting her back to her home on the Queen’s Crescent estate, Belsey finds the missing man is an obsessed fan and stalker of Amber Knight, a talented singer and actress who lives close by in a Primrose Hill mansion.

Using his charisma and a knowledge of how to make people give him the information he needs, we then follow Belsey on a fast-paced journey as he tries to figure out why people keep dying, and the dark secret that connects characters who otherwise move in very different circles.

Harris said tackling the world of celebrity was a natural next step after writing about corruption in the Bishop’s Avenue, and London’s little-known underground network of abandoned tunnels in his previous two Belsey novels: The Hollow Man, and Deep Shelter.

Harris explains: “We take it for granted, living here, but it is one of the world’s big celebrity hotspots, so I love the idea of Nick Belsey crashing into that world and having his 15 minutes of fame, uninvited.”

But Harris confesses that the glitzy celebrity universe was not something he knew much about before researching the book.

Rather than basing any of the celebrity or socialite characters in the book on any real-life famous personas, Harris instead turned to the library, and gossip magazines.

“I got out all these memoirs, these biographies, but they were all so dull that I couldn’t actually find anything interesting details. I wanted the reality and it was really hard to find,” Harris says.

“But I realised that the whole point is that there isn’t any big secret to it, it’s just people with an entourage, making a lot of money and managing that business while it lasts.

As ever with writing, what you want is the mundane details and they’re the hardest thing to find. I also realised, that you know where celebrities hang out, if you spend life in north west London.” Without giving too much away, The House of Fame ends with Belsey arriving at the airport.

Harris has just returned from a trip to Mexico to research the fourth book in the series.

But rest assured, Harris says Belsey will be returning to his native north London before too long, as Hampstead and its environs have always proved an irresistible draw for Harris.

“I knew I wanted to write a detective novel about London, and coming back to Hampstead after no longer being there, I was really struck by the conspicuous wealth but also by the sense of what that masked. Where there’s money, there’s darkness.

“I love noir, and no-one had really painted Hampstead in those colours. But there’s a lot more corruption on the surface there than you get in Hackney or Tottenham. Those big houses don’t come out of nothing.”

The House of Fame, published by Jonathan Cape, is released on April 14 in hardback and e-book (£12.99).

Harris will give a talk at West End Lane Books on April 21. Free but call 0207 431 3770 or email info@welbooks.co.uk to book.