Is one of television's most popular franchises a dead show walking?

That is the fear as hit zombie romp The Walking Dead returns for an eighth season at the end of the month. Buffeted by on-set tragedy, a wave of lawsuits and tumbling ratings, there are genuine concerns the AMC smash (airing on Fox in Ireland) might be in terminal decline.

This summer was supposed to be when The Walking Dead took stock and renewed itself after an unsteady several years. Instead, its crisis grew even more pronounced with the July 3 death of stuntman John Bernecker.

Bernecker (33) tumbled more than 20 feet from a balcony onto concrete flooring during the filming of a scene at The Walking Dead's Georgia base. An experienced professional, he had worked on the Hunger Games, Logan and Marvel's upcoming Black Panther.

The circumstances in which he died were questioned by Bernecker's girlfriend Jennifer Cocker (also a veteran stunt performer). She expressed concern, in particular, about the presence on the balcony beside Bernecker of actor Austin Amelio (who plays anti-hero Dwight). As quoted in the Hollywood Reporter, Cocker believed Bernecker should not have been left alone with a stunt newcomer "who doesn't know what he's doing".

Production was shut down for a week but the show ultimately had to go on. Quite what sort of show will return on October 23 remains to be seen, however. Last year The Walking Dead generated controversy of the worst sort with a flurry of early violence, as two beloved characters, Glenn and Abraham, were messily killed off (Glenn's eyeball was bashed from its socket, while his skull was reduced to a strawberry-hued smear).

There was an outcry, with many fans taking to Twitter to declare they would never again tune in. Ratings duly plunged an astonishing 40 per cent. By the end of the season viewership had slumped to a five year low and media commentators were questioning The Walking Dead's future. Yet the show-runners, were not for turning.

"I don't think we would have done it any differently," Greg Nicotero, director of the notorious Glenn and Abraham episode, told me when I met him earlier this year. "It serves the purpose of the story."

"If you look at any other show - whether that be Game Of Thrones or Breaking Bad, it's the same. We don't do it to be gratuitous even though people might look at it that way. To me that's not what is shocking. What is shocking is the next morning and these people are sitting in a circle completely broken."

In the background, meanwhile, a long running legal dispute may be about to blow up in the face of AMC. Original show-runner Frank Darabont - better known as director of The Shawshank Redemption and The Green Mile - is suing the network claiming it has structured its business in such a way as to deny him payments he contends are rightly his (he was conspicuously ousted from the production in its second season). A similar series of lawsuits was recently lodged by other producers still working on the series, asserting AMC is employing murky bookkeeping to likewise shortchange them.

"Rather than a referendum on me, this lawsuit is about AMC's radically undervaluing The Walking Dead in order not to share profits in a manner reflecting the show's actual fair market value", said Darabont in legal documents. "This lawsuit is also about AMC's refusal to share the unprecedented success of the show with the people who actually created that success for them, and about AMC's self-dealing and corporate greed."

AMC has pushed back hard. "These kinds of lawsuits are fairly common in entertainment and they all have one thing in common - they follow success," went a statement from the network. "Virtually every studio that has had a successful show has been the target of litigation like this, and The Walking Dead has been the #1 show on television for five years in a row, so this is no surprise."

Still, perhaps it would be premature to proclaim last rites on Walking Dead. There is genuine excitement among the fan community with the promise of a resolution to the ongoing battle between Sheriff Nick Grimes (Andrew Lincoln) and the post apocalyptic Saviour gang and its charismatic leader Negan (Jeffrey Dean Morgan). Moreover, every television series of any longevity suffers the occasional wobble - even the hallowed Game of Thrones endured a backlash this year after one plot convolution too far.

Moreover, The Walking Dead has always been a punch bag for critics. Where Game Of Thrones - its rival for title of world's most popular drama - has wooed opinion-formers with its lush production values and gratuitous nudity, The Walking Dead's slow-burn bleakness is a more acquired taste. The haters are lining up to take a pop - but those involved in The Walking Dead will argue this is merely more of the same.

"We're gonna write the show we're gonna write," Nicotero told me. "If people react to it one way or another that's never going to change what these actors do. We are absolutely dedicated to telling the story we want to tell. For someone to say 'oh, you used the wrong colour in that painting - no, THAT's the colour."

The Walking Dead returns to Fox on October 23