Midsomer Murders star reacts to big twist in scarecrow episode

But in a shocking twist, it emerged that there wasn't just one killer running rampant, but a grand total of three: Naomi was killed by Rachel (real name Lisa), while her father and the reverend Oscar was murdered by Jack, and Thea was hammered to death by Samira.

Adele was next on their list, but the police managed to stop the culprits before they could do their worst.

Speaking to RadioTimes.com, Nick Hendrix, who stars as Detective Sergeant Jamie Winter, said: "The challenge with something like Midsomer is: how do you keep it the same, but also make it different each time? And often there is just one murderer who's often killed one person by accident or a crime of passion, and then they've killed two more people to try and cover their tracks.

"And the idea of having multiple murderers just makes it a little more interesting, I think, and a little trickier because sometimes it feels too easy – well, not easy, but too well put together when Barnaby and Winter join the dots by the end, and it all comes together. So it's quite nice to have that different take on it.

"We're always trying to think of ways to break the tropes and break the pattern, while also keeping it the same. We always have red herrings. Everyone is basically a suspect. You don't really have any characters that aren't suspicious in some way, so I thought it was good. I thought it was clever and hopefully we keep doing that, keep trying to reinvent the wheel."

Naomi, Oscar and Thea were killed because of their involvement with Ventuity, an online casino founded by Adele. Naomi handled the PR, Oscar was a major shareholder and Thea was the customer relations manager.

But while Ventuity had benefitted the trio, fattening their pockets substantially, it had left the murderers' lives in tatters.

Lisa's son racked up so much debt that he took his own life at the age of 20, while Jack's dad had used payday loans to gamble with Ventuity, which resulted in him losing his house. He tried to stop, but the company wouldn't leave him alone, just as Thea had given Samira a number of free bets, despite knowing she was desperately trying to break her destructive habit.

They met in an online forum and began joking about what they wanted to do to Naomi, Oscar, Thea and Adele, before turning their shared fantasy into a reality.

"The other thing with the show is we try to always modernise and stay current while also honouring the history," said Hendrix. "And by bringing in themes like that, like gambling addiction, there is a sort of gentle nod towards current issues."

Speaking about the series celebrating its 25th anniversary, Hendrix added: "Somehow, over 25 years and however many episodes, Midsomer's managed to maintain the standard.

"We're filming one right now and it feels and looks and is written just as well and eccentrically and playfully as every other episode. From 25 years ago to now, they've managed to maintain that somehow, even though they've changed actors, changed producers, changed writers over the years.

"You know what you're getting with Midsomer. People like a bit of stability in what they watch on TV sometimes. I don't know about you, but I always spend ages sitting in front of the TV [deciding what to watch].

"There’s a bit of stress and admin around that. And sometimes people just go, 'Midsomer's on,' and there's no debate about what it's going to be like, or whether they're going to enjoy it or not. They just know what they're going to get.

"We like new, cutting edge things but people also like stability, people like a friendly face, a reliable, trusted source, and I think Midsomer is that.

“And also, everyone loves a whodunnit. Everyone loves to try and solve a mystery. It doesn't have to be set anywhere in particular. People just love that."

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