Sinéad Keenan on Unforgotten: 'What eejit is going to follow Nicola Walker?'

"A few months later, I was on holiday and got a phone call from my agent: 'The people from Unforgotten want to send out scripts to three people and you're one of them. Would you read it?' I was very quick to say no, thank you very much. Because what eejit is going to follow Nicola Walker? No, I don't think so."

But the 45-year-old's agent was persistent. "She said, 'Look, I've read it and it's very good. Please just read the first script.' And I was like, ‘OK, fine.’ And sure enough, I read it, called back and said, 'Er, is there another script knocking around? Because I just really want to know what happens!'

"Then I met the team, who were lovely. They very kindly asked, 'Would you do it?' and I said, 'Go on then.' That was it. Now I'm literally the eejit who's following Nicola Walker."

The eagerly awaited new season opens with a grisly discovery up a chimney in Hammersmith, West London. Was Keenan on a beach somewhere exotic reading this?

"The first call from my agent came when I was looking after my two kids in a toy shop in Portugal," she laughs. "Actually, I was lucky to be by the pool when I read the script. But it was compelling, as [series creator] Chris Lang's scripts always are."

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Had she also seen the three previous seasons which made Unforgotten a slow-burning hit? "I hadn't, only because I'm late to every party," she admits. “But I went back and watched them. God, it’s good. It’s no wonder the show’s so blooming popular.”

Which was her favourite series? “Four, I thought, was brilliant. But also the first one, with Gemma Jones and Tom Courtenay’s confessional. Then again, there was heartbreaking Mark Bonnar in series 2 and Alex Jennings in series 3. What. A. Psychopath.

"They’re all great and my God, the casts. It's testament to the writing, the calibre of actor they get in. It’s no wonder because it’s all there in the scripts. Everything starts and ends with a great story, which Unforgotten delivers.”

Another attraction was the premise of a cold case police procedural. "I liked that idea because there's some family grieving somewhere," she nods. "It's important to give people dignity in death, to find out what's happened to them and give closure to their loved ones."

After earning a BAFTA nomination and winning an RTS Award for her devastating portrayal of Melanie Jones – mother of murdered Liverpool schoolboy Rhys – in 2017's acclaimed Little Boy Blue, it's a subject close to Keenan's heart.

Keenan was pleasantly surprised to retain her own Irish tones for the Unforgotten role. "I usually don't use my own accent," she says. "When they approached me, I assumed it would be an English accent but Chris really wanted me to keep the Dublin one.

"It was odd at first because I'm not used to hearing myself like that when I'm working. I was like, 'Who's that and why does she sound so awful?' On the plus side, there was enough to worry about without mastering another accent as well."

When we first meet Keenan's character, DCI Jessica James, she’s in the midst of a domestic drama. "Her first day in her new job certainly doesn't go the way she'd hoped," agrees Keenan.

"On the way into work that morning, something happens which knocks her completely off-kilter, which doesn't help when she's going into a team who are not only grieving the loss of a colleague but of a friend.

"They're greeted with this shadow of a DCI who's not up to scratch, which naturally doesn't go down well. Jessica's usually great at her job - very on-point, good at managing teams - but that all goes to pot because she's shellshocked and blindsided."

Hang on, didn't Keenan’s character in 2021 legal drama Showtrial also have a wild west name? "That's right, it was DI Paula 'Butch' Cassidy," Keenan laughs. "First Butch Cassidy, now Jessie James. There's definitely a theme here. I clearly give off cowboy vibes. Maybe all my jobs will be westerns from now on."

Did playing a cop in Showtrial help prepare her for Unforgotten? "Not really," she says. "They're such contrasting characters and different styles of show that the fact that they're both detectives is fairly incidental, despite them sharing cowboy-ish names."

DCI James certainly isn't a like-for-like replacement for Cassie. Firstly, she seems to have little interest in solving historic murders. Was the intention to wrong-foot everyone? "Oh, completely," says Keenan. "They're grieving and it's mirroring what the audience is doing, mourning the loss of Cassie, the loss of Nicola.

"To add insult to injury, this seemingly inept person takes over from someone who was held in such high esteem and much-loved, especially by Sunny [right-hand man DI Sunil Khan, played by Sanjeev Bhaskar]. Viewers will and should feel annoyed by that. But as the story develops, Sunny and Jessica eventually get into their own particular groove."

The chemistry between Cassie and Sunny was key to Unforgotten's success. How does the new double act develop? "They're wary of each other, understandably," explains Keenan. "Initially, Jessica goes in and is a little cack-handed. She tries to make jokes but they don't land. Nothing she does is working.

"He's also a bit sarky with her. There's a brilliant line at the end of the first episode where Sunny puts Jessica in her place. That's only human. It's what happens in real-life. They're both in a bad place, taking it out on each other."

Despite the dark subject matter, the cast and crew managed to keep the mood light. "There was lots of laughter on set," Keenan smiles. "And I have to say, 99.9% of that came from Sanjeev. Between takes, you just wind him up and let him run. It was constant anecdotes and hilarious stories. He's a really lovely, fun person to be around."

Keenan says she's "fully prepared" for Unforgotten fans taking time to adjust. "It's a bit like if your parents split up and your dad brings home a new girlfriend. You're like, 'Nah, I will not be liking you.'

"That's probably a poor analogy because Cassie was killed, obviously, but Chris has been clever about introducing Jess. The audience aren't kept in the dark. They know from the get-go why she's acting the way she is, otherwise there'd be uproar. It might take a while, but hopefully viewers will enjoy it by the end."

Will Jessie return for season 6? "Well, I do know that Chris has a plotline and everything ready for a further series. We just need to wait for the grown-ups to decide."

Is it true that a TV legal drama first made Keenan want to become an actress? "Yes, Matlock! This '80s series starring Andy Griffith in his white suit, looking a bit like Colonel Sanders, always doing these grandstanding speeches in court. I used to love it as a kid and thought I might study law. Until I realised that was a lot of work and I'd rather play the character instead."

Her fascination with criminal cases has never quite left her: "I do enjoy a good true-crime podcast, I must admit. It all started with Serial back in the day. My latest binges were The Teacher's Pet and its sequel The Teacher's Trial. The same investigative journalist, Hedley Thomas, also did Shandee's Legacy. I'm not fanatical, but do find them compelling."

Last year, Keenan popped up in the final season of Derry Girls as ex-con Aideen O'Shea, the third episode's titular 'Stranger on a Train'. "That was brilliant fun," she chuckles. "Lisa McGee wrote a sitcom I did called London Irish, back before Derry Girls were born. I've known her for years and she's so clever, so I was delighted to go back and do a little stint."

Keenan's breakthrough role came in cult BBC Three supernatural drama Being Human back in 2009. For three seasons, she played nurse-turned-werewolf Nina, girlfriend of Russell Tovey's George.

Has she stayed in touch with her former castmates? "There isn't a Honolulu Heights WhatsApp group, sadly, but I do keep in touch with lovely Russell, who's still filming in New York as we speak.

"He's finished American Horror Story and has now moved onto another big Ryan Murphy production about Truman Capote [Feud: Capote's Women]. He's got his Talk Art podcast too, so he's doing brilliantly. I can’t wait to see him when he comes back.”

What's next for Keenan herself? "The honest answer is, I don't know," she says. "Something will turn up. I need to get back to that Portuguese toy shop with my children and wait for the phone to ring." She laughs again. "Maybe I'll continue the cowboy theme and it'll be Annie Get Your Gun."

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Unforgotten airs weekly on ITV1 from Monday 27th February at 9pm. The complete series will be streaming as a boxset on ITVX after the first episode airs.

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