Broadchurch turns 10: Chris Chibnall on the drama that gripped the nation

There were newspaper splashes, bets, sweepstakes, and the nation was hooked in a way that has only happened a handful of times since. A decade on from the first ever episode, Chibnall has exclusively opened up to RadioTimes.com about just how it happened.

Part of the magic of it (the "alchemy", as Chibnall puts it) was the cast: Tennant, Colman, Jodie Whittaker, Andrew Buchan, Pauline Quirke, Vicky McClure, Jonathan Bailey - and the list goes on.

"We had Olivia in mind, definitely. She was one of the first names on the whiteboard, when I was putting up all the characters," Chibnall recalls.

"But it just came about through various processes. We had an incredible pair of casting directors, Victor [Jenkins] and Kelly [Valentine Hendry], who were just completely fantastic. And they made lists, suggested people, brought people in, people read and people were really up for it as well, that's what we were really surprised by.

"Because they also didn't get a full set of scripts. I think it was only episode 1 most of them read, maybe it was slightly more for someone like Pauline Quirke, but not much. And they all had to take it on trust. It was just astonishing. You look at someone like Vicky McClure coming in, doing that part [reporter Karen White], Jonathan Bailey, all those people. I feel really blessed."

Recalling meeting Colman for the first time, Chibnall is quick to admit: "We were so desperate for her to do it. It was me and Jane Featherstone, the exec producer. We're sitting in this place waiting for Olivia. And we were like, 'If she asks, should we tell her who did it?' Because we've agreed to keep it secret from everyone. But obviously we were like, 'No, no, we mustn't.'

"When she sat down, she said, 'I've got two questions - do we find out who did it and can I kick him in the balls?' We were like, 'OK, it's your husband and yes!' So you know, we both crumbled at the first step."

"David, we were really lucky to get him," Chibnall continues. "I mean, obviously, because he's the busiest man in film and television. There were parts in America and it just worked out with the timing but I mean, you never know what's going to happen with acting chemistry on set.

"There was one two-hander scene we had with them early on in the show, and it's where Olivia’s character Ellie invites David's character Hardy for dinner. And it was the rushes of that scene, and they were so funny, and they were both so brilliant...

"They were so funny, so amazing and so true. I think they unlocked it because they also have that thing - I was really keen on making sure there was still humour and light and energy within a really dark and troubling story. They’re just wonderful together."

Another essential element of that magic was secrecy, something the future Doctor Who showrunner would have to get very used to. He knew from the early stages of drafting the script that Ellie's husband Joe was going to be the killer - but it was essential to tell as few people as possible. So, other than Colman, none of the cast knew.

"That was a big part of it. Even during filming, [the actors] didn't know until the final episode script came out. So they had their own sweepstake, there were charts on the walls in the trailers and the make-up truck. It was just an approach I suggested we take by instinct really, but also I knew that it would stand or fall on people engaging with that and really kind of relishing that. We just sort of played every trick in the book.

"The weekly nature of it just enabled people time to speculate on it and make up their own theories. The whole structure of broadcasting and ITV were really central to that - even the ad breaks and the cliffhangers were all very deliberately constructed."

Those very good reasons to keep the killer secret did nothing to quell Tennant's outrage when he discovered that Colman had known from the beginning though. "Later on, David found out, quite near the end, that she'd known all along. He went bursting into her trailer, going, 'You knew!'"

The main fear was that the shock ending, the reveal of Joe Miller as the killer, would leak. It was such a monumental ending that Chibnall had no alternatives in mind.

"Right when I was writing the very first draft, I thought it was someone else [a different minor character] and then after I'd written that, I put the script aside and then a week or two later I woke up with that in my head going, 'Oh, that makes everything make sense, and become exciting, become emotional.'

"Because the whodunnit aspect was really important, but obviously the emotional nature of it and the emotional psychology of the show, I think, is what people responded to, and you wanted to serve all those amazing actors. Because that's the other thing, that was part of the huge appeal, is you just had some of the best actors in Britain all in one show.

"No, it was always him, because it gave Olivia's character a really great arc, and lots of characters a really great arc, because of that."

Chibnall did change some parts though. "There were things I expanded on, the story of David Bradley's character Jack, who runs the newsagent. That was a slightly smaller aspect when I was writing it and then when we got to the storyline involving him and his death, it needed more space. It became much more pivotal in terms of the middle section of the first series.

"And because David Bradley is one of the most beautiful, wondrous actors you could ever hope to [see] and he was breaking your heart on screen. I still think about that confrontation with him and Andy Buchan, who played Mark, where David Bradley says, 'He was a good boy' about Danny. It gives me chills, still. It was such a beautiful performance."

Even with that extraordinary mix of factors, Broadchurch was still far from a guaranteed hit.

"It was a massive risk for ITV because they've really mainly done kind of episodic drama and that was what was working. They were very supportive, 'We love the show, we believe in it.'

"But eight weeks on a Monday night at nine o'clock felt like the most massive risk and, because it was a serial, if people didn't see episode 1, then it really wasn't going to go anywhere. We could have been on at half past midnight by episode 4."

Of course, that didn't happen - quite the opposite.

"Week one and week two, it was really solid. And then I think week three it went up, and your shows never go up in week three. And then there started to be articles in the news section of the newspapers. It'd be stuff about West Bay and Clevedon, the two places we filmed it, and then it was like the bookies were starting to take odds on who had done it. And it just started to take on its own life. And yeah, from there, it was a rollercoaster," Chibnall recalled.

"I think about week three, week four, the frenzy had begun and that snowball never really stopped rolling until the end - well, even after the end it carried on - but that was the point. People would stop me in the street and go, 'Who did it?' Or if I was on the phone to somebody or booking a taxi - 'We'll send a taxi but you've got to tell us who did it.'

"It was genuinely mad and delightful. But also completely weird to be at the eye of the storm. It was just profoundly odd. And I remember the Head of Drama at ITV, Laura Mackie, saying to me in week five, she's like, 'This never happens. So make sure you enjoy it because it's so rare.'"

Broadchurch was so successful that it lived on in various other adaptations, most prominently the US series Gracepoint. While he's thrilled it had such longevity, Chibnall doesn't have any plans for it to return in the immediate future.

"I think you'd have to project 20 years forward to a time when you could get David Tennant and Olivia Colman in the same room again! If there was a story in 100 years time... I don't know, there's certainly no immediate prospect of that. What we did, we loved - I don't have any more to offer you than that!"

He's never been tempted, either, even after the huge success of the show.

"I didn't really have a story that felt like it needed telling in that world. I really wanted to do the story of the first season – the story of the second season was all about how the trial often re-traumatises families in these cases, based on a lot of research, and the third season again, before we even went ahead with it, we did a lot of research, talked to a lot of people, a lot of organisations, and it felt like those stories were around in the national zeitgeist at the time and people were talking about them. You can't do that forever. It just felt like the right point to stop."

A decade on, Chibnall is proudest of the fact that it was a "great piece of teamwork" and that it connected with audiences so well.

"I'm pleased it came out of nowhere, I'm pleased it connected with people and I'm pleased that people are even wanting to talk about it 10 years on. That's kind of incredible."

Broadchurch seasons 1-3 are available to stream now on ITVX. Check out more of our Drama coverage or visit our TV Guide and Streaming Guide to see what's on tonight.

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