James Norton on bursting into tears reading Joy script and Happy Valley memories

Norton plays Robert Edwards, one of three scientists who teamed up in the 1960s and '70s to invent the process of in vitro fertilisation (IVF), in the face of much opposition from the press, Church and even other scientists.

Thorne and Mason – and director Ben Taylor – are themselves beneficiaries of the vital work that Edwards, Patrick Steptoe (Bill Nighy) and Jean Purdy (Thomasin McKenzie) achieved, so it's a film incredibly dear to those who made it.

And speaking exclusively to RadioTimes.com, Norton reveals he was so moved by the script that he delayed a summer holiday to star in it.

"It was sort of early in a summer where I was coming off the back of a job, and it was a long and very, very stressful play," he explains.

Everyone he spoke with had told him he was clearly in need of a break, but as soon as the script landed on his desk, he knew the "delicious" combination of writers, director and cast mates was going to be too good to turn down, even if he admits to a couple of early doubts regarding just how entertaining the story might be on screen.

"I read the tagline, I think, 'This is about these scientists who discovered IVF... it's got to be pretty boring.' Like, how are you going to find a drama in that? There's no conflict, there's no kind of antagonist," he says.

"[Then] obviously, I read it [and] burst into tears many times. It was such a moving read, Jack and Rachel both have been through the IVF journey, as has Ben... so much personal experience, so much warmth and heart in the script. So then it was like, 'OK, put my summer holiday on hold for a second.'"

Norton himself says many people in his life have been through IVF, such that he now knows "many little people, babies and toddlers" born of the procedure. But he was relatively unaware of the origin story behind the scientific breakthrough and the opposition its innovators faced at the time, and quickly became convinced of the importance of giving them the credit they deserve.

The personal experience of Thorne, Mason and Taylor also ensured that the experience of making the film was an especially profound one, and made the stakes that little bit higher for everyone involved.

"People were coming to work, going home and tucking up these babies that wouldn't be with us otherwise, you know, the world would be devoid of that love," he says. "And then you multiply that by 12 million [an estimated 12 million children have been born of IVF].

"Ben is currently shooting in Albuquerque and he was telling me how hard it is to be away from his kids. That man is full of love for his children. Jack and Rachel love Eliot so much. And a world without that love is just mad. And so it really did bring home how, on the tiny, micro level, important this science is. It's just astounding how much joy this particular piece of scientific progress has brought."

The film's title is taken from the middle name given to Louise Brown – the very first IVF baby – but it sounds like it was also an accurate description of the process of making the movie. Norton struck up an especially great relationship with co-stars Nighy and McKenzie, with the trio forging a friendship that seems to go beyond the usual bond formed by actors on a project.

"It was really lovely," he smiles. "Bill Nighy... he's like the nation's cosy grandfather, isn't he? I mean, he'd probably hate me saying that, but he's like, well, a kind of cool uncle... like, he's a national treasure.

"And he'd also definitely hate me saying that, but he's just a lovely, lovely man, and is full of anecdotes and wise words, but also like sparkle and wit and just a complete pleasure to hang out with in the green room.

"And you know, I'd had a tough summer, and I thought I needed a rest. And actually, I think what I needed to do was hang out with Bill Nighy! And then Thomasin McKenzie is just such a wonderful actress, and now a dear, dear friend. We had a lot of fun. I just remember feeling it was a very happy set and Bill, Thomasin and I have stayed friends.

"We've got a WhatsApp group called the fallopians. We go for dinner a lot. We've remained friends. Sometimes on a film set, you fall in love with each other, and then you sort of say goodbye, 'We'll stay in touch.' You never do. Bill, Thomasin and I do stay in touch, and we are going to dinner. And it's a testament to how much we did replicate the camaraderie and closeness of those three on screen."

Although now heralded as important visionaries, Edwards, Steptoe and Purdy all faced backlash for pursuing their goal in spite of the growing fear-mongering from the press – with the latter even jeopardising her relationship with her fiercely religious mother.

But as the visible face of the group, the one tasked with making media appearances to explain their work, Edwards arguably had to deal with the fallout of their project in the most public way.

Norton is full of admiration for all three, calling them "trailblazers" and "disruptors" who "we owe so much to". And he was especially in awe of the ways in which they made such major personal sacrifices to ensure that their project would be a success, something that he's not sure he'd have managed personally.

"I'm a people pleaser, and the idea of kind of going into the world and going into society knowing that you're going to displease most people is incredibly brave," he says. "And yet it was so important, and he knew how important it was.

"What's really interesting for me as well about Bob was that he had five daughters, so it wasn't like he had any experience of the infertility journey at all. He was actually the opposite. He had been blessed with these five incredible, healthy children. But I think that's really what his engine was as well. He knew the joy that those kids had brought him, and he knew that everyone, if they wanted, children, should have the right to that opportunity.

"But in terms of the pushback, not only did it take incredible amounts of time, energy, sacrifice, time away from his family, at the detriment of his relationships with his kids and his wife. It also took – for all three of them – it took this kind of insane determination, [and] they had to displease the people they loved and upset the people they loved, like Jean's mother.

"And that's an even bigger sacrifice, really. That's remarkable that they were able to see how important this was, and that was the cost they were willing to pay."

One of the most enjoyable aspects of the role was digging into the man beyond the science, with Edwards portrayed as an affable but slightly odd character (one scene sees Purdy affectionately calling him a "very strange man").

Norton heard all sorts of fun anecdotes while he was preparing to play him – some of which he says "were actually inappropriate, because they were so eccentric" – but the thing that came across most was just how much people were drawn to him.

"He was just loved, like, he really was loved, and the people who worked with him fed off his enthusiasm and his energy," he explains. "He wrote a book with Patrick called A Matter of Life and Patrick's contributions are really dry and kind of, you know, quite specific science.

"Bob's are like... just so sort of flamboyant, and you can feel this Labrador energy bouncing off the page in a complete antithetical tone to Patrick. So that was quite helpful [for] finding a voice for me!"

One other thing that came across from the research was how determined Edwards had been to see Purdy – whose work on the project had often been overlooked – given proper recognition. A post-script in the film explains how he campaigned tirelessly for her name to be included on a plaque outside Kershaw's Hospital, where the bulk of their work had been carried out, with this wish finally coming true in 2015, two years after his death and three decades after Purdy's.

Given that determination, does he reckon Edwards would have been happy to see the release of a film which very much puts Purdy at the centre of the story?

"I hope so," he says. "I mean, we wouldn't be making this... obviously, we wouldn't be making this film if Bob, Patrick and Jean hadn't done what they did in the 1960s and '70s in terms of IVF. [But] I wonder if we would be making it at all if it hadn't been for Bob's campaign to get Jean recognised, because that was actually the way in that the film needed, the story needed.

"There have been various attempts to make this film, to tell this story, and I think the reason it hasn't quite worked to date is because people assume you have to come from the point of view of the scientists and Bob and Patrick, who are the known names.

"And actually, the genius stroke is to come at it rightfully from Jean Purdy and the women in the Ovum Club [a group of women who served as early test subjects in IVF trials], really the celebration of their sacrifice. So, I mean, Bob would be very happy that Jean was honoured, for sure. Whether he would be or is happy with my portrayal of him, who knows? I hope so. I did my best to get to the heart of his warmth and goodness."

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As mentioned above, Norton has had a great deal of variety in his film and TV projects – other highlights of which include a long-running part in Grantchester, a leading turn in the BBC's 2016 version of War & Peace, and a supporting role in Greta Gerwig's beloved Oscar-nominated adaptation of Little Women.

It's therefore no surprise that he's got a number of very different projects in the pipeline. Very soon he'll be seen in new ITV drama Playing Nice, while beyond that he's got two very different historical dramas on the way: King and Conquerer, and House of Guinness.

The former dramatises the Battle of Hastings and its build-up and sees him star as Harold of Wessex opposite Nikolaj Coster-Waldau's William the Conqueror. It's an especially personal project for Norton given he's also on board as a producer, and he describes the process of taking it on from the concept stage as "a real journey".

"I've been developing it for about six, seven years, and it's been percolating," he explains. "We've been having meetings. We've been talking to directors, writers. You know, it's been a long, long journey."

He continues that Mike Johnson, the lead writer of the series, had brought the idea to him and a couple of other producers seven years ago. "And to have gone from that one meeting with one sheet of A4 [as a] pitch, to then being on the mountain in Iceland with the Saxon army facing off the Norman army... And that's another story which, bizarrely, has never been told on film – we've never seen a Battle of Hastings drama!"

House of Guinness, on the other hand, sees him team up with Peaky Blinders boss Steven Knight to tell a story about the moment in the 19th century that the beloved stout brand started to become such an international phenomenon. Norton teases that Knight is "at his best" with the show, and promises a "really fun" series.

"It's got beer. It's got this eccentric family. We've got these Steven Knight characters all kind of jostling and playing, fighting, f**king. It's just, like, really exciting!" he says.

That's the future, but what about the past? Now that he's had a bit of distance from the electrifying reaction to the Happy Valley finale, I wonder how he looks back on his time on the show and the ecstatic response it provoked from both punters and critics. Did he see it coming?

Norton speaks incredibly passionately about those memories, and says that it was clear from the outset that they were "making something really special" with the closing scene.

"I remember that day, the whole studio were, like, really quiet," he recalls. "Usually it's quite noisy, and there's gossip and there's banging and clattering. And that day felt like we were in a church, because everyone knew that we had come to this moment where these two characters had this face-off, and everyone had read the script. There wasn't any false endings, those were all rumours.

"We knew what was going to happen. The fire brigade were there because, you know, the burning, so everyone was just charged. And then Sarah [Lancashire] comes in, one of the greatest actresses living, giving one of her greatest performances. And I just remember sitting there going, 'F**k me. It does not get better than this. This is amazing!'"

Bringing things back to the present, and the release of Joy, Norton hopes that, above all else, the film makes people give appropriate respect to Edwards, Steptoe, Purdy and anyone else who is willing to be disliked for the greater good.

"Lots of people have nudged us into a conversation around the current climate around these conversations," he adds. "And I think for me, the biggest takeaway from this film is the cost that it had on not just Bob and Patrick, but particularly Jean – she died at 39 and she didn't have children of her own.

"She dedicated her life to this. She died in Bourne Hall. They put a room aside for her, and she died surrounded by mothers or women who had gone through the IVF process, surrounding her – that was her family.

"She gave everything to this, but also the women who were in the Ovum Club, those women who didn't get children and who went through multiple rounds, put their bodies through that... the huge cost paid by these people for the future generations.

"And then we live in a time when that is now being threatened, and we see how fragile that is. And this film, for me, the biggest thing was we must protect that progress at all costs, because it is fragile and it is invaluable. So the fact that we have fought for choice, we must protect."

Joy is now showing in select UK cinemas and will be released on Netflix on Friday 22nd November 2024 – sign up from £4.99 a month. Netflix is also available on Sky Glass and Virgin Media Stream.

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