Sam Heughan and Eleanor Tomlinson on the "debaucherous fun" of The Couple Next Door

Both actors are period-drama veterans – Tomlinson played Demelza Poldark for six years, while Heughan has played Jamie Fraser for almost ten, and is about to start filming series eight of the popular show. But the pair have far more in common than their roles in 18th-century costume dramas: they also have many mutual friends – including Caitríona Balfe, who plays Jamie’s wife, Claire, in Outlander.

All of which made teaming up for Channel 4’s new psychological thriller, The Couple Next Door, a no-brainer. Five minutes into our conversation (Tomlinson is speaking over Zoom from her home in London; Heughan is speaking over Zoom from his New York hotel), it’s clear that their friendship is genuine and close, built on mutual respect for each other’s work, as well as a shared sense of humour.

"Caitríona knew El before I did," smiles Heughan. "So I’m already jealous of that situation. I want to say that El is my best friend, not Caitríona’s. But that’s something Caitríona and I will fight over on set." Tomlinson, meanwhile, describes working with Heughan as "debaucherous fun".

Debaucherous fun is something the characters in The Couple Next Door very much aspire to, even if it often eludes them. When university sweethearts Evie (Tomlinson) and Pete (Alfred Enoch) move to a cookie-cutter street in a fictitious suburb of Leeds (though the show was largely shot in Antwerp), they’re immediately befriended by Becka (Jessica De Gouw), a beguiling yoga teacher, and her equally beguiling partner Danny (played by Heughan), a traffic cop.

But like most suburban streets, theirs harbours myriad secrets. Things are definitely not what they seem. And soon a wedge comes between Evie and her husband, hurtling the mild-mannered primary school teacher down a path she might not otherwise have taken. But let’s not spoil things by revealing more.

"It was a real treat – very different for me," says 31-year-old Tomlinson of her reasons for taking the part. "Working opposite Sam, and us both having come from period dramas was a real draw. I’m excited to turn people’s opinions of us on their heads, and show that we can do something very different."

"Not having to wear a corset!" jokes Heughan, 43, of his own reasons for signing on. "Not that I wear one every day [on Outlander], but most days. Obviously Outlander is a huge production. You can spend a whole day on one scene, and that’s great, but it was so nice to go on this show, which was so fast-moving and organic. That comes down to the crew and the way the piece works, but it was refreshing to do something completely different and to work with a really core group of actors and cast."

They agree that playing contemporary characters is no easier than playing period ones. "I wouldn’t say so, because I didn’t know anything about being a teacher," says Tomlinson. "There was quite a lot of research to do. I called a couple of my friends who are teachers to ask them about protocol. Just as with a period drama, you learn the etiquette. Your performance has to be real, or people don’t relate to you."

To research the part of Danny, Heughan spent time with a traffic policeman who worked for Police Scotland. "He was really generous with his time, walking me through procedures. They’re always the first responders [to a road accident], and there are effects of working in such an intense job."

Unusually for a show that – spoiler alert – features its fair share of sex, Tomlinson and Heughan didn’t have to do any chemistry tests before being cast in The Couple Next Door. "We didn’t at all," says Tomlinson. "We just talked through the characters, and the vision for the series. I’d been a big fan of Sam for a long time, so when the opportunity came to work with him, it was like a jigsaw piece falling into place.

"And then Jessica and Alfred came on board, and I realised it was a really sexy 'core four'. In terms of chemistry tests, we worked through that during rehearsal time before we started shooting, and also on set before each scene." Which feels like a good time to ask: what actually is a chemistry test? "Undoubtedly, Sam will have done more than I have, so I’ll let him answer that one!" laughs Tomlinson.

"I always find them such a strange thing," Heughan admits. "Producers do like to look for chemistry [between actors], but if I’m totally honest, I don’t really know, if you’re an actor, whether you feel this chemistry or not. When you’re in the moment, you’re not thinking, 'Oh, is there chemistry here?' –you’re just in it."

They worked with a "brilliant" intimacy coordinator, Vanessa Coffey, whom Heughan suggested, having worked with her on Outlander’s sex scenes, which have won praise for their sensitivity. "Everybody felt comfortable," says Tomlinson. "The way that the sex scenes are shot isn’t necessarily what you would expect. I was keen to get across [the idea] that you can make something just as sexy by implying it."

"I think we both have a great deal of experience with that perspective," laughs Heughan. "Period dramas are different worlds. I knew Vanessa was great, and had a really nice demeanour about her on set. I think we’ve both maybe struggled in the past with [sex]scenes, and how to portray them without giving away too much or feeling uncomfortable. It was great to push these scenes and make them feel intimate for the viewer without making it really difficult to shoot."

The curtain-twitching, status-obsessed claustrophobia of suburbia is well captured by Belgian director Dries Vos, whom Heughan worked with on last year’s James Nesbitt drama Suspect. And both lead actors agree that moving to the suburbs isn’t, perhaps, as aspirational as it was.

"It’s hard for people to live in suburbia because everything is so expensive," notes Tomlinson, who married rugby player Will Owen last summer. "And as this show proves, once you’re inside the dream, the reality is different. You get up, leave for work at the same time, and that’s what scares people, that fear of falling into a pattern and not knowing how to get out of it."

"But some people choose that life," says Heughan. "Danny and Becka chose it to bring up their child, because they feel it’s a safe environment, but it’s all falling down around him. It might look idyllic, but underneath, we find out it’s a lot more choppy."

Have either of them experienced life in suburbia, or is it on their bucket list? "I certainly don’t want the life that’s in our show, no. I was raised in Yorkshire, and that was lovely. But it wasn’t suburbia as it’s portrayed here," says Tomlinson.

"My mum’s an artist, I went to a Steiner school, so I guess I had a slightly alternative lifestyle," says Heughan of his upbringing in Dumfries and Edinburgh. "If you choose to become an actor, it’s not your regular, typical life. We all thrive with a bit of stability and routine. Like all of us, I want family, a great relationship and a partner that understands me, but no, I don’t think it’s the life that I want."

As the show explores, relationships are rarely straightforward, but when I jokingly ask them their opinions of swinging (not as off-topic as it seems – it’s part of the plot), they are defensive. "I don’t think it’s necessarily swinging as such, it’s more an exploration of non-monogamy, and how to keep a relationship vibrant. There are deeper relationships and mental journeys going on with each individual character," says Tomlinson.

"I would say a relationship that perhaps has wider boundaries than other traditional ones is actually a representation of true love," adds Heughan, who is currently single. "To be able to be in love with someone so much that you allow them to explore other situations is the most romantic thing, in a weird way."

So non-monogamy could be the key to an idyllic relationship? "I have no idea what the key to an idyllic relationship is," he laughs. "Perhaps someone can tell me sometime."

He’s probably too busy to give it much thought. In 2020, he co-wrote, with Outlander co-star Graham McTavish, Clanlands, an international bestseller, and also launched Sassenach Spirits, whose whisky and gin has won numerous awards.

"Outlander gave me a great opportunity to go home, and also promote Scotland to the rest of the world. It’s a great country, so I’m claiming myself as an unofficial ambassador. Anywhere you go, people love Scotland. Almost as much as they love Yorkshire," he winks.

As for the immediate future, Tomlinson has "two very exciting projects coming out next year" that she’s unable to talk about, while Heughan is poised to film the final season of Outlander, a show destined to leave as many broken hearts, when it ends, as Poldark did. "Mine included," says Heughan. "It’s going to be hard to leave it after such a long time. But everything has to come to an end. I just hope that we end it with satisfaction. We want it to be the best one yet."

If he needs advice on how to recalibrate, he has Tomlinson to turn to. "We’ve spoken about it quite a lot," she says. "It is going to be a huge change. But I’m at the end of the phone if you need me."

"If I could turn out even slightly like her by the end of it, I’d be happy," Heughan smiles. "Just not as ginger."

The Couple Next Door airs on Channel 4 in the UK from Monday 27th November, and on STARZ in the US in 2024. If you're looking for more to watch, check out our TV Guide and Streaming Guide or visit our Drama hub for more news and features.

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