Now the final series of Inspector Morse prequel Endeavour has ended there is a gap in the market for an Oxford-based crime drama on TV.

At least four million viewers tuned in to the final Endeavour on Sunday, the culmination of Colin Dexter's Morse franchise, which started out with the Inspector Morse TV series in 1987.

The Inspector Morse, Lewis and Endeavour TV series have all generated millions in tourism cash coming to the city.

Now Endeavour, starring Shaun Evans and Roger Allam, has concluded, viewers are wondering what might replace it.

ITV will have plenty of options but for an Oxford-based crime drama they should not overlook the popular crime novels of Cara Hunter.

Her six novels featuring Di Adam Fawley could be adapted for TV after a deal was struck for the rights to the series in 2020.

This is Oxfordshire:

Ms Hunter’s series of crime novels set in the city have been incredibly successful following the publication of her debut Close To Home in 2017 and someone in the world buys one of her thrillers every 50 seconds.

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Manchester-based drama company Castlefield, part of media company Fremantle, picked up the rights to writer Ms Hunter’s novels for a TV adaptation.

Ms Hunter, who lives in north Oxford, said in 2020: “I’ve always ‘seen’ the Fawley books play out in my head as I write them, and the style I developed for them was a deliberate attempt to replicate the feel and pace of the best TV crime – the short scenes, the fast pace, and the changing points of view."

Castlefield was launched in June 2019 by managing director Hilary Martin and creative director Simon Judd.

The independent drama label, based in Manchester, focuses on edgy and emotionally compelling contemporary drama series, that have global appeal.

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Ms Hunter added: “Hilary and Simon completely ‘get’ what the books are all about and have a wonderful feel for the characters. I can’t think of a better producer for the series than Castlefield.”

This is Oxfordshire:

The author’s six-book franchise is the biggest crime-writing brand to have launched in the UK in the last five years, selling more tha one million copies to date in the UK and across 25 territories worldwide.

Her debut novel Close to Home was an international bestseller, topping The Sunday Times and Amazon bestseller lists and was publisher Penguin Random House’s biggest selling eBook of 2018.

At the heart of each DI Fawley thriller is a domestic tragedy or crime in Oxford that demands answers from the family and friends of the victim.

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With echoes of real-life crime stories, the writer toys with our expectations and turns them on their head with her carefully plotted, twisting storylines, coupled with the engaging drama of the professional and personal lives of Fawley’s team.

Ms Martin and Mr Judd joined Fremantle in 2017 and in their previous roles at BBC Drama North, Hilary and Simon developed and produced shows including BAFTA-winning In the Flesh and James Herbert’s The Secret of Crickley Hall.

This is Oxfordshire:

In a joint statement they said in 2020: “We are so thrilled to be joining forces with the brilliantly talented Cara Hunter to bring her hit novels to screen.

"Cara collides noisy, epic crime stories with vivid, visceral characters that you just can’t look away from.

"Her razor-sharp depiction of contemporary life is a gift.”

The franchise could become a multi-episode series, and there could be more than one series, once it is attached to a broadcaster.

The author said in a tweet last summer that a TV adaptation was 'still in script development.'