Oxford-based Endeavour is back on ITV but are these the last mysteries for Morse?

There has been speculation that the TV drama will not get another series, marking the end of an era of TV dramas based on Colin Dexter's Inspector Morse novels.

But ITV has refused to confirm yet that the eighth series of Endeavour, starting on Sunday, will be the end.

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Shaun Evans reprises his role as DS Endeavour Morse, alongside Roger Allam as DCI Fred Thursday for three new compelling cases written and created by Russell Lewis.

Produced by Mammoth Screen, part of ITV Studios, in partnership with Masterpiece, series eight is produced by James Levison.

Mr Levison said: “A huge amount of work by all the team goes into making a series of Endeavour, and never has that been truer than this season with the strict Covid protocols we had in place to ensure everyone’s safety when coming to work.

"The whole process brought another layer of detail that was embraced by every department, not just the new Covid department.

"I am very proud to be part of a team that were so diligent and supportive of each other to safely bring another ambitious season of Endeavour to its fans. "That hard work and dedication under the current climate comes across in three brilliant Endeavour films that I hope audiences will love.”

John Thaw became recognised around the globe as Oxford-based Inspector Morse, thanks to the ITV series which ran between 1987 and 2000.

The actor died in 2002 but his memory lives on and while he had many roles it is perhaps as Morse that he is best known.

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Episodes of the Inspector Morse sequel Lewis, starring Kevin Whately and Laurence Fox, ran from 2006 until ITV announced in 2015 the ninth series would be the last.

Endeavour focusing on Morse's early career as a detective was launched in 2012.

Filmed on location in Oxford, the strong ensemble cast for series eight includes Anton Lesser who returns as CS Reginald Bright, Sean Rigby as DS Jim Strange, James Bradshaw as Dr Max DeBryn, Abigail Thaw as Dorothea Frazil, Caroline O’Neill as Win Thursday and Sara Vickers as Joan Thursday.

The year 1971 has just begun and the team’s first case gets off to an explosive start as they investigate a college bomb with possible links to recent IRA threats.

And a death threat to Oxford Wanderers' star striker Jack Swift places Endeavour and his team at the heart of the glitz and glamour of 1970s football, exposing the true cost of success and celebrity, and with it, a deep-rooted division that is soon reflected much closer to home.

Series seven of Endeavour averaged 6.1 million viewers across all devices across its three episodes.

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Chief executive officer and founder of Mammoth Screen Damien Timmer is the executive producer alongside Russell Lewis, Shaun Evans, Roger Allam, Mammoth Screen’s Director of Television Helen Ziegler and Rebecca Eaton and Susanne Simpson at Masterpiece.

Award winner Ian Aryeh and Kate Saxon joined the production to direct series eight.

Mammoth Screen is one of the UK’s leading production companies.

Series eight starts on ITV on Sunday at 8pm.

There have now been 33 episodes of Endeavour filmed - the same number as the Inspector Morse series.

Asked if series eight would be the last Shaun Evans said: "That’s a decision for the whole team. As we have always done, we need to finish this series, take a look at them, take a view over what was done well, if there’s still a story to tell and if we all still want to tell it. So, we’ll see."