Happy Valley creator Sally Wainwright on the "definite climax" of season 3

So, no more Catherine sitting at the back door with her sister Clare, played by the excellent Siobhan Finneran, having a cup of tea and a cigarette. No more of the fractious but fragile Ryan, the grandson Catherine is bringing up because her daughter took her own life after she was raped by Tommy Lee Royce. And no more of the psychopathic Tommy, portrayed to perfection by James Norton, trying to get close to Ryan, despite Catherine’s best efforts to stop him.

The third season is just starting and it’s easy to feel bereft. Since Happy Valley first aired in 2014, Wainwright’s beautifully drawn characters have become part of the fabric of our lives.

Of course, we’ve already had to wait nearly seven years for the latest episodes. What took so long? Talking on the phone from her home outside Oxford, Wainwright laughs. "During a large part of the hiatus I was writing and directing Gentleman Jack, which is such an intense project. I had to read and transcribe Anne Lister’s diaries and turn them into a dramatic narrative.

"After season 2 of Happy Valley, I had a pretty clear idea of what I wanted to do next. It involved Ryan being old enough to have some agency in the world and to have some more developed opinions about his dad."

It’s a shock to see Ryan reappear as a strapping 16-year-old lad with a deep voice, but all the central cast have returned for the final run and the continuity really works – when the family sit around Catherine’s dining table in the first episode, it’s like seeing old friends.

"I’m glad it feels like that," says Wainwright. "There was a conversation about recasting Ryan, but Rhys [Connah] was keen to play the part again and he’s great. I think we’d have had a very different show if we’d recast. It wouldn’t have had the same feeling because Rhys has a lovely vulnerability about him."

Wainwright sees the world in a very particular way – as it is. Growing up in Sowerby Bridge in West Yorkshire, she wrote strip cartoons and then plays with her sister and, even at the age of seven, was drawn to the dialogue as "the most alive thing".

After graduating from York University with a degree in English, she wrote for The Archers and Coronation Street, a discipline that led Corrie alumni such as the late Kay Mellor, Paul Abbott and Wainwright herself to create socio-political drama that is also funny.

Happy Valley is often seen, rather lazily, as "gritty", but that overlooks what Wainwright does so well – humour. She’s included it in every drama she’s written, from At Home with the Braithwaites to Scott & Bailey and Last Tango in Halifax, but there’s something exceptional about the humour in Happy Valley, which comes at unexpected moments and really hits home.

She’s pleased to hear this, but then confesses to feeling nervous about replicating the huge success of seasons 1 and 2. “I was really anxious not to write a duff third season. I really don’t think it is. There’s a very definite climax.

"A narrative has gone across all three: in season 1, Catherine and Tommy came face to face outside Ryan’s school, and in season 2 they almost came face to face in the crematorium, at Tommy’s mum’s funeral. In season 3, there’s a very big face-to-face showdown. The kind of cathartic showdown that people have waited for." She laughs. "It’s pretty dramatic."

Tommy Lee Royce is, once again, the disrupter in Happy Valley, albeit with a different look – this time he’s gone full-on Jesus, with long hair, a beard and scars. There has always been an odd kind of chemistry between Tommy and Catherine, which makes it impossible to look away when they’re on screen.

"I guess that, from a writer’s point of view, the chemistry between them is [created by] presenting each character as they would like to present themselves. So even though Tommy does these terrible things, I always wanted to be fair to him and show why he does them. He’s cursed with this psychopathic brain.

"As Ryan says a couple of times in this season, ‘Tommy was born like that, it’s not his fault.’ And Catherine agrees with him, but she says that’s why you have to throw away the key."

In the first season, Tommy beat Catherine up and, of course, the tabloids complained. But Wainwright was in fact very careful about her depiction of violence; it wasn’t gratuitous but rather mirrored real life.

"I worked on Happy Valley with a police adviser called Lisa Farrand. She was pretty cross with some of that criticism because it’s the reality of being a cop; she’s been badly beaten up twice and nearly killed once. To not reflect it in a drama that is realistic about what it’s like to be a female police officer would be a whitewash."

It’s not as though Wainwright had no previous experience of writing cop dramas; in fact, she was approached by the BBC to write what became Happy Valley following the success of Scott & Bailey, ITV’s police procedural that starred Suranne Jones and Lesley Sharp as detectives. What was her starting point? “I wanted to make it different from Scott & Bailey, so the most obvious thing was to have someone in uniform.

"I was heavily influenced by Juliet Bravo [BBC1 1980–85], which I watched as a teen. Nurse Jackie [the US comedy drama] had a profound effect on me and I wanted to create my own Jackie Peyton, by turning her into a police officer.

"There was also a 2009 documentary called Shed Your Tears and Walk Away by Jez Lewis, about the drug and alcohol culture in Hebden Bridge among a certain age group. It’s really heart-breaking but brilliant. I got the cast to watch it before we started filming season 1. It helped set the tone for what we were trying to achieve."

In recent years, Wainwright started directing as well as writing. To date, she’s written, directed and produced more than half a dozen episodes of Happy Valley and Gentleman Jack and a drama about the Brontë sisters, To Walk Invisible. Directing has to be the antidote to writing, surely?

"It’s the complete opposite. Writing is very lonesome and I love nothing more than being on my own. I’m not a sociable person. I recently decided that I’m slightly autistic and that social interaction is actually quite painful for me. But when I’m directing, because there’s so much to talk about, so much intensity and detail, I come alive. It’s the only time I feel like I’m good at being sociable."

Her desire to direct grew from the frustration of handing the script over to someone who doesn’t always get it in the same way that she does. She also acknowledges that there’s still a paucity of female directors because women don’t think it’s their right to stand behind a camera.

“I think it requires confidence, but also it takes a certain type of woman to direct. It’s about having an incredibly tough mindset. I don’t have a thick skin, so I have to consciously put on a coat of armour and not take anything as an insult or negative comment.”

Despite Wainwright’s phenomenal success – Happy Valley alone has five Baftas – she still occasionally faces frustration. HBO, who co-produced Gentleman Jack with the BBC, has pulled out after just two seasons, despite a dedicated fanbase. It was "a real passion project" for Wainwright and she’s currently exploring other options for funding.

In the meantime, she’s written another historical drama, The Ballad of Renegade Nell, for Disney Plus. It follows the adventures of an 18th century character who becomes the most infamous highwaywoman in the country and stars Louisa Harland, Joely Richardson and Adrian Lester. Wainwright says she loves doing research and jokingly refers to herself as a "keen amateur historian".

For now, however, the world will be watching the final season of Happy Valley. Since we can’t talk about the plotlines for fear of spoilers, we talk about Catherine being such a pleasure to spend time with. "She’s basically a very funny, competent woman to whom something very tragic has happened. The older a character gets, the more likely they are to have those complexities."

Above all, Wainwright has written the kind of person that so many of us want to be mates with. She laughs. "Well, I create characters that I want to be or that I want as mates. That’s part of the fun of being a writer – you can invent all these invisible friends."

Happy Valley season 3 continues on Sundays at 9pm on BBC One and BBC iPlayer. The first two seasons are available to watch on BBC iPlayer now.

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