Miss Scarlet will be missing the Duke as star exits ahead of season 5

So, going forward, the show will now be known as Miss Scarlet from season 5, with actress Kate Phillips reprising her now sole lead role as Miss Eliza Scarlet.

The news will undoubtedly come as a surprise to fans of the period drama, who have watched over the previous four seasons to find out what cases our Victorian era detectives will face.

Announcing his departure from the series, Martin said in a statement on Thursday (29th February): "It has been such an incredible joy to bring Duke to life through [series creator] Rachael [New]’s beautiful, brilliant writing, and to get to play him for the past four years.

"But it felt like the time was right for Scarlet to explore new stories and challenges for now, as the show continues to grow and evolve.

"I will miss working with my amazing partner in crime Kate and the rest of our brilliant family and team, but I’m excited to continue following Eliza and her escapades as a huge fan and newly enrolled Scarleteer!"

Phillips also said in her own statement: "I will miss working with my pal Stu every day, and know Eliza will miss her Duke, but I think the best is yet to come for her. I can’t wait for fans to see what we have in store for season 5."

But Phillips won't be coming back to the series by herself, as returning cast members include Evan McCabe as Detective Fitzroy, Cathy Belton as Ivy, Felix Scott as Patrick Nash, Paul Bazely as Clarence, Simon Ludders as Mr Potts and Tim Chipping as Detective Phelps.

It's safe to say that the news has shocked longtime fans of the show, with many taking to X (formerly known as Twitter) to express their thoughts over the upcoming season.

One fan wrote: "I loved watching Miss Scarlet& the Duke! I loved William & his character! & most importantly their romance, the slow burn...why make him finally confess he loves her if he was leaving? S05 will be about Eliza & her cases? Or watch her fall for someone else?"

Another commented: "This one annoys me to no end. It's literally Miss Scarlet AND THE DUKE."

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Production for the new season is currently underway in Belgrade, Serbia, with a release date for season 5 yet to be announced – but there's still plenty in store for Miss Scarlet.

As series creator Rachael New has said of the news: "We will miss our Duke, but there is so much in store for Eliza – new crimes, new friends, new foes and new romance. We will be keeping her very busy!"

Debuting back in 2020, the show follows Miss Scarlet, who was initially left penniless after her father unexpectedly died.

She resolved to take over her father's detective agency alone, and would call on William, aka the Duke, to aid her in her cases as he worked at Scotland Yard.

Over the seasons, the pair have faced numerous cases together and developed an increasingly close relationship – whether we'll see this addressed at all in season 5, we'll just have to wait and see.

Miss Scarlet season 5 will air on Alibi in the UK and on PBS in the US. Check out more of our Drama coverage or visit our TV Guide and Streaming Guide to find out what's on.

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