Death in Paradise: The show critics hate and audiences love celebrates 100 episodes

It remains one of the BBC's most-watched series and is broadcast in over 200 territories around the world.

The 100th episode, which launches its 13th season, features a nod to those early criticisms when the current Brit-copper-on-the-island Neville (Ralf Little) muses that he would like to start a blog about his adventures in the Caribbean. Despite his enthusiasm, local officer Marlon (Tahj Miles) politely tells his boss that such a subject is a "bit on the boring side".

"It's a little in-joke," explains executive producer Tim Key. "Would you be interested in watching a story about a British detective in the Caribbean? The answer, it seems, is lots of people are quite interested in it."

As fans know, each episode follows a similar formula – a murder is committed in the opening pre-credits scene, a series of red herrings, clues and suspects are explored by the Saint Marie police team, and then in a flash of genius, our detective figures out the crime and assembles all the suspects to explain whodunit, how and why.

Over the years, a variety of murderous methods have been employed to strike down countless individuals, including poisonings (cyanide and puffer fish venom are among the deadly liquids, plus a Seinfeld-style poisoned envelope), being chucked off a cliff, electrocution in a swimming pool, and a stabbing with an ice pick.

But despite the high mortality rate, Death in Paradise is still a show the entire family can watch (most of the murders occur off-screen, occasionally signalled by a distant scream), which Key believes is one of the secrets to the series' success.

"There aren't many shows that know exactly what they are and set out to unashamedly entertain the audience in such an intriguing and uplifting and warm in every sense and funny but heartfelt way," he says.

"I think we've been blessed with some amazing actors playing really interesting characters. There's an escapism, there's a parlour game mystery to play along with, there's just a lot of lovely things that have all come together and created something that feels very, very special.

"And that becomes an appointment to view for our audience and something that starts the year off in a nice way when the weather's appalling."

While the basic formula of the show remains the same, there have been obvious evolutions over the past 13 years, with the most notable being the role of the British lead detective, which has been recast three times since its debut.

Little's Neville Parker is the fourth British detective to move to the island, following on from original officer Poole (who was murdered at the start of season 3), Humphrey Goodman (played by Kris Marshall, whose character has since relocated to Devon in spin-off Beyond Paradise), and Jack Mooney (Ardal O'Hanlon, whose character returned to London in season 7).

"Kris came in to replace Ben [Miller] and it worked, then it was amazing with each lead actor bringing their own sort of flavour in there," Key says. "But also every time we do it, it is absolutely terrifying, because we're very aware of the affection that the audience has towards that lead character."

And it's not just the lead actors that have changed over 100 episodes, as he notes. There have been subtler alterations over the years, too.

"I think the challenge with the show all the time is how to change it and not to change it – how to make sure the audience always gets the hits that they expect from Death in Paradise," Key explains, adding that there are some more surprises to watch out for in the current series.

"Every episode will still have this mystery puzzle, but we've innovated the way we do those," he says. "We've got some really cool ones this year, where they aren't necessarily done quite as you might expect them to be.

"And I think we've done more serial stories with our [regular] characters – we've taken our lead characters increasingly on quite profound journeys. Back in the earlier days of the show, although there was a bit of serial, it was much more heavily about the story of the week.

"Now, there's increased focus on the lives of our characters, and I think that's the luxury we have – to be able to surprise people like we did last year by bringing in Selwyn's daughter. You see another side to him, he's suddenly a father, and is coming to terms with that."

Key adds: "We've got a great cast and also this luxury of the history that the audience have with the show. Where can we take them? What can we do now? How can we really change the characters? So I do think it has changed a lot, and also kind of not changed at all."

Death in Paradise is also famous for the impressive list of guest stars who have popped up on screen over the years, with recognisable faces such as comedian Jason Manford, Line of Duty's Martin Compston and Adrian Dunbar, numerous soap stars including Lisa Faulkner and Patsy Kensit, and even a Bond star, Samantha Bond, all having visited the island for an episode (the new series also features screen legend Hayley Mills and singer/actress Kate Robbins, as well as Sean Maguire reprising his role from the first ever episode).

"I don't think many of the guest cast need persuading [to come out to Guadeloupe for filming]," laughs Key. "They are very happy to come and join us and they have a good time. They are usually here between a week and a fortnight and we work them quite hard. But obviously there are days when they are less busy and can enjoy the sunshine!"

Key has a wish list of actors he would love to feature in future episodes, too. "Robert [Thorogood], who created the series, said to me he really wanted to get an actual Dame in the show, and I don't think we've achieved that yet. So I'm working on that."

Surely Dame Joan Collins is a name that's cropped up?

"She's been mentioned before," he replies with a smile.

And of course, a celebration of 100 episodes of Death in Paradise wouldn't be complete without a mention of the show's most memorable guest star of all, Harry the lizard, who lives at the detective inspector's bungalow and makes regular appearances in the series.

"People are very disappointed when they find out Harry is CGI," Key says. "He's the longest living lizard! Maybe someone should make a documentary about him.

"And I'm still very proud of that CGI, if it is still fooling people. The team that worked on him at one stage, I think, had also done the Godzilla movie. So I think they learned a lot from that and Harry got more realistic at that point.

"Not bigger, though – he didn't start destroying Saint Marie or anything."

Death in Paradise season 13 will arrive on Sunday 4th February. Every season of Death in Paradise is available to stream now on BBC iPlayer.

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