How did the real DI Steve Fulcher and the victims' families help shape ITV drama A Confession?

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• When is A Confession on TV? Who’s in the cast? What’s it about?
• What are the real-life events behind ITV’s true crime drama A Confession?

A Confession is written by Jeff Pope, the Bafta-winning screenwriter behind See No Evil: The Moors Murders in 2006 as well as This is Personal: The Hunt for the Yorkshire Ripper in 2000. He's also the man behind Cilla, Mrs Biggs and Little Boy Blue.

But what did he get from talking to the real Steve Fulcher, and the parents of the two victims? And did they give their blessing?

Here's what Pope, Freeman and director Paul Andrew Williams had to say at a screening in London – and what Sian's brother Liam O'Callaghan told us ahead of the show's launch on Monday 2nd September...

Was the real Steve Fulcher involved in A Confession?

Writer Jeff Pope made contact with Steve Fulcher early in the TV show's development, and also read Fulcher's 2017 book Catching a Serial Killer: My Hunt for Murderer Christopher Halliwell.

But though he spent plenty of time with Fulcher going over his experiences, he was keen not to take the former detective's word for anything – talking to other police officers and those involved in the case.

"We got together – and first thing to say is, I didn't take his word as gospel," Pope says. "He wrote a book, which I read, and I used that as a starting point to try and knock down all aspects of it. That said, I did spend an awful lot of time with him because I needed to understand what had happened."

Martin Freeman, who plays Fulcher, says: "Well, I met him before we started shooting. We had a sort of rehearsal day with Paul [the director] and I met Steve that day... so we just kind of went through his story again, his side of all this."

He adds: "I occasionally texted him when there was a scene coming up... obviously he wasn't directing me. He came down to set a couple of times but he wasn't in charge or anything!

"But it was nice to have the horse's mouth, to just kind of go: what were you feeling there when you were having this meeting with this bloke who you knew was trying to screw you over? What, emotionally, were you feeling? And he's very forthcoming, he's not backwards in coming forwards about how he felt and how he feels about that stuff. It was really useful. I think that was the first time I've ever had that opportunity with a living person."

"Watching it with him afterwards was almost unbearable," Pope says, recalling the moment he showed Fulcher footage of the drama. "He was kind of crawling up the walls, he just found it so difficult."

Turning to Freeman, Pope adds: "You'd managed to take him straight back into the most awful events in his life."

Were the families of the victims involved in making A Confession?

At the centre of A Confession are the families of Sian O'Callaghan and Becky Godden-Edwards, who were both murdered by taxi driver Christopher Halliwell.

Sian's mother Elaine Pickford is played on screen by Siobhan Finneran, while Becky's mother Karen Edwards is portrayed by Imelda Staunton.

They are joined by Sian's boyfriend Kevin Reape (Charlie Cooper), her brother Liam O'Callaghan (Jake Davies), and father Mick O'Callaghan (Ian Puleston-Davies). From Becky's family, we also meet her father John Godden (Christopher Fulford) and Karen's partner Charlie (Peter Wight).

Each of those people exists in real life, and will now see one of the most tragic periods of their lives played out on screen.

"If Elaine and her family and Karen and her family had not wanted me to do it, then I wouldn't have done it. Because I just don't think, morally, you can ride roughshod over people who've suffered that kind of loss," Jeff Pope says. He worked closely with the victims' families from the very beginning, setting up a meeting in London with the O'Callaghans.

Sian's older brother Liam O'Callaghan tells RadioTimes.com: "He thought that there was quite a compelling drama to be told and a story to be told, and would we be happy to be involved in it? Would we be supportive? And then following from that chat and further discussions, we gave our full support."

Liam adds: "If I'm honest, after our first meeting I did start to do a little bit of homework on Jeff! Based upon what he was going to produce, the complete story that he was potentially going to tell, I felt that it needed to be in capable hands, it needed to be accurate, we needed to be involved. And after doing the research and seeing what he'd done with Little Boy Blue, having watched that, it felt like, this is the right person to do this story."

At first, he says, the family was "a bit apprehensive, and a little bit worried about how we may be depicted. But because we felt that there was, particularly from a family standpoint, a need particularly for Fulcher's story to be explained, that we were fully supportive. As soon as we knew that that was going to be the focus."

Jeff Pope adds: "The big things from Elaine and Liam and their families' point of view is, they didn't want Sian forevermore to just be thought of as a victim. There was this girl, having a lovely life, in the middle of a family that loved her, and then she's taken away. Horribly and suddenly and shockingly. And she's now that girl in the photo - the victim. And so the big thing, actually Liam's big thing, is he wanted her to be a person not just a figurehead... so I tried to work Sian in, not just 'that girl that was murdered'."

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As for the experience of seeing his family's story on TV, Liam says: "It is surreal. It does take you back obviously, it's difficult times, so it puts you into kind of a strange headspace I suppose. But the way in which the actors and actresses have portrayed us is fantastic, we met with them, they told us they're not going to do a like for like, they took certain mannerisms and just wanted to get an idea of who we were as individuals, which would help them in this piece, and I think their portrayals are fantastic."

Talking to Elaine and Karen was hugely important for getting those small (but crucial) details right – like the relationship between the two bereaved mothers, who had such different personalities and attitudes to their own grief.

Director Paul Andrew Williams reminds Pope: "There was a point where you did think that they did come together at the end [of the drama] and have a hug."

"Talking about it with one of the mums, saying, 'You come here and you hug,'" Pope recalls. "And they were like, 'No. No. That didn't happen.'"

He explains: "One of the reasons why Sian's mum wanted to take part is she wanted to signal to people that, God forbid they're ever in that situation, it's okay to grieve however your mind or your body is telling you to grieve. That's okay."

So the reality was that the two mothers did not bond in a neat, TV-friendly way. "But in a way that for me is equally as interesting to see. It just wasn't meant to be. You don't have to be friends with anyone. Grief is quite personal."

A Confession begins on Monday 2 September at 9pm on ITV