Can Shetland survive without Jimmy Perez?

While the series initially worked directly from Ann Cleeves's source material, several of the seasons in recent years have moved away from adapting her work, which leaves the team behind it free to write as they see fit, which will now include appointing a new lead.

There's a possibility that the executive producers could pass the baton to a fan favourite supporting character, such as Alison O'Donnell's Tosh, who has been a key player in all six seasons to date. That would echo the trajectory of Inspector Lewis, which focused on Inspector Morse's sidekick and was not based on Colin Dexter's writing.

But despite the success of the ITV series, which spanned nine seasons – a greater lifespan than its parent series – it feels unlikely that a Shetland spin-off is on the cards.

There's also the possibility of Shetland following in The Bay's footsteps, with the ITV drama bringing in Marsha Thomason following Morven Christie's exit. That would give the series space to observe the island with a fresh pair of eyes, offering new avenues for discovery and, crucially, tension.

The introduction of a newcomer would also inject the show with a fresh feel and tone, as is the case with the addition of each lead detective in Death in Paradise.

Regardless of who takes the reigns, the shift in tone or personality might prove off-putting for audiences. While Tosh and Sandy (Steven Robertson) have quirks and traits that make them standout characters who offer an interesting counter to Perez, are they suited to being the central focus? A new addition also poses the same unknown. However confident the Shetland bosses are in their decision, it will be the viewers who decide if they've chosen correctly.

Perez's exit could also signal the end of the road for other characters, such as Mark Bonnar's Duncan, who is heavily tied to the lead due to their Cassie connection. While the show is first and foremost a detective series, the human side of Perez and his relationships is a central part of its appeal and continued success. To ensure that remains a key aspect of the narrative moving forwards, the creative team behind it will need to establish a similar heart and focus with whoever the new lead is.

If we do see Bonnar and other core cast members exit, Shetland's long-term survival would undoubtedly be under threat, with a mass exodus likely proving too drastic a shift, both for audiences and also those who operate behind-the-scenes.

The ultimate question is whether a new lead can maintain the acute interest that has resulted in six seasons of the show to date, with two more instalments on their way? With the novels and subsequent series built around Perez, will audiences be able – or willing – to embrace change?

There's currently ample appetite for it to continue in the short term, and the BBC is confident it can continue the story in season 8. But beyond that, it's unknown if Henshall's exit has signalled the beginning of the end.

Shetland season 7 begins in August 2022 on BBC One and BBC iPlayer. Ann Cleeves's Shetland novels are available to buy now.

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