‘My husband has to remind me: You’re not a real cop!’ Siân Brooke on the perils of playing a tough Blue Lights ‘peeler’

Sharp eyes save lives. That’s the mantra of the police officers in Blue Lights, although the words sound a good deal more urgent when said in a throaty Belfast accent. The city, dealing with past and present problems, is the turbulent setting for the hit drama. Having starred in the BBC series for the past four years, Siân Brooke has taken its lessons about vigilance to heart.

“I noticed some dodgy-looking activity not far from where we live in London,” says Brooke. “I’d driven past a few times and was suspicious. I told my husband that the last time I went past, I slowed down and did a drive-by, so they’d know their untoward behaviour had been rumbled. My husband said: ‘You can’t do that, Siân. You’re not a real cop!’” She laughs. “I think Blue Lights has got to me. What was I going to do, make a citizen’s arrest?”

Brooke was Bafta-nominated this year for her leading role as Constable Grace Ellis: a social worker and single mother who switches career in her 40s to join the Police Service of Northern Ireland (PSNI). As the acclaimed drama returns – for a fourth series taglined “their toughest shift yet” – viewers are flung straight into the action as protests outside a migrant centre erupt into a full-blown riot.

“There’s an intense energy to filming those high-octane sequences,” says Brooke. “Adrenaline pumps through you. I injured my elbow but didn’t notice until I had to pull my gun and couldn’t do it. I needed steroid injections.” Could such fearless dedication to stunt work make Brooke the new Tom Cruise? “I’m glad you noticed,” she grins. “The only difference is he jumps off cliffs, whereas I pulled a muscle picking up a wheelie bin.”

The scenes proved eerily prescient. Weeks after filming them in spring, anti-immigration riots broke out on the streets of Belfast for real. “That was remarkable,” she says. “Our writers really do their research and have their fingers on the pulse. That’s partly why their scripts are so good. They’re urgent, authentic, almost documentary-style.” This could also be because Declan Lawn and Adam Patterson, the show’s writers and co-creators, are former Panorama journalists.

Police advisers ensure that Blue Lights gets the finer details right. “They’re always on set. That day, we had people who worked in public order policing. They explained the protocols and how to manage disturbances. After four years, our experts have become a key part of the team. They’re very open about their experiences and how they affected them. That feeds into the show.”

Such commitment to realism meant firearms courses for the cast. “We had weapons training before series one. We were rookie actors playing rookie police officers, so it made sense. Now the armourers give us regular refreshers: how to hold our guns, where to rest your trigger finger and the like.”

Equally challenging is wearing the PSNI uniform, with its bulky stab vest and tactical belt. “My goodness, there’s so much paraphernalia,” says Brooke. “You’d think they might have streamlined it by now. I’ve asked real officers: ‘How do you run with all that stuff on?’ Apparently everything just flies off. When they’re chasing baddies down the street, their pepper spray is propelled one way and their notebook another.”

It certainly isn’t a costume that screams glamour. “Not the most flattering,” she agrees. “During filming, my flak jacket wouldn’t behave. Every time I got into the squad car, it would ride up until I resembled a Teenage Mutant Ninja Turtle. The costume department ended up putting in a piece of wood to weigh it down. For two series, I was walking around with a chopping board down my jacket. Everyone would knock on it and make wisecracks about my acting being wooden.”

Importantly, the show has the seal of approval from Brooke’s father. “He was in the force for many years and when I first got the role I sent him the scripts. I thought it captured the camaraderie and banter. He agreed and has been a big fan ever since. He’ll binge the new series. Being able to talk much more about his career has been an unexpected gift from this. Police officers often tell me they’re touched by how the show shines a light on the difficulties of the job.” Brooke is even inspiring the next generation: “A friend’s daughter has said she wants to join the police because of Blue Lights.”

One theme in the upcoming series is social media’s ability to mobilise communities – something worryingly close to home for Brooke’s character. “Someone reveals Grace’s identity online and puts her safety at risk. Social media is scary. I worry about its addictive nature and its impact on society, especially as a mum to two teenagers. I recently did [cyber-thriller] The Undeclared War about how social media infiltrates politics. It’s frightening stuff.”

On screen, her partner is Sergeant Stevie Neil, played by Martin McCann. As half of one of TV’s sweetest couples, is she ever asked for relationship advice by fans? “No, thankfully!” she laughs. “Maybe me and Martin should start a column in the Guardian. Would you have us as guest agony aunts? Grace and Stevie on middle-aged romances in the workplace.”

After Brooke had a decade of success on stage, her TV breakthrough came in 2017. She’d played Ophelia opposite Benedict Cumberbatch in Hamlet at London’s Barbican then reunited with him in BBC blockbuster Sherlock. She auditioned for three roles before being told they were all the same character: the sleuth’s secret sister Eurus, a master of disguise.

“Having been a genuine fan of Sherlock, I had to pinch myself,” she recalls. “My sole objective was: ‘Don’t mess it up.’ It was mad being in the midst of Sherlockmania. Oddly enough, my kids are now of an age where they’ve started watching Sherlock from the start. It’ll blow their minds when they get to series four. They might disown me.”

Brooke shone briefly but brightly in HBO’s Game of Thrones prequel, House of the Dragon, playing Queen Aemma Arryn, first wife of King Viserys. Was she disappointed to die so graphically during childbirth in the first episode? “It was a shame because I would’ve loved to ride a dragon! I turned the page of the script and was like: ‘Oh well.’ She definitely made an impact though. It wasn’t short and sweet. It was short and violent.”

Brooke has steadily worked her way to becoming one of TV’s top-tier performers. Her current hot streak includes scene-stealing turns in Netflix superhero drama Supacell as shadowy bureaucrat Victoria Kesh (“Her villainy definitely cranks up in the second series”) and Apple comedy Trying as the overopinionated Karen (“I love playing someone so deliciously forthright”). Next up is fact-based ITV drama Mavis Eccleston. Due early next year, it’s a poignant account of the 80-year-old woman who survived a 2018 suicide pact with her terminally ill husband before being accused and found not guilty of his murder.

“It’s a sensitively told story about this loving family,” says Brooke. “A big pull for me was that it all happened 20 minutes from where I grew up in Lichfield. As a Staffordshire girl, you don’t get many stories that local.” Penelope Wilton plays Mavis, with Jonathan Pryce as her husband Dennis. Brooke is their daughter Joy, someone the actor has met several times. “She’s warm, kind and naturally very protective of her parents’ story. The care she shows her mum is inspiring. You feel a huge sense of responsibility playing real people.”

Did it change Brooke’s view of assisted dying? “For me, everybody should be able to give themselves the ending they wish. It’s their life and their right. It didn’t change my opinion but it did give me greater understanding of the complexities. I’m hoping it sparks conversations at home.”

Mention of Lichfield brings to mind her Instagram bio’s declaration of “Midlander”. Is she proud of her roots? “Very proud but it wasn’t always that way. When I came down to study at Rada, it seemed that being from Manchester, Glasgow or Dublin gave you a strong identity. Somehow it wasn’t the case with the Midlands. I was slightly at sea for the first chunk of my career. A bit lost and didn’t know what my voice was. With age, I’ve claimed my heritage. Maybe it’s the Peaky Blinders effect, but it feels cool now. I want to champion stories from the Midlands.”

She’s an ambassador for two charities close to her heart. While researching a Blue Lights storyline, she forged a relationship with Belfast-based Macs, which helps young people with homelessness and leaving the care system. Climate change adaptation group the Glacier Trust is currently dealing with the aftermath of the flash floods in Nepal. “Both organisations are brilliant,” she says. “Working with them is just my tiny offering.”

Having worked nonstop for 15 months, Brooke felt she’d earned her break this summer. “It’s been a glorious period of work but it was lovely to spend time with my kids. Although I suspect they got fed up with me by the end. Six weeks off school is maybe a week too long. I’d advocate for five weeks and adding an extra week to the October half-term.” The campaign for Siân Brooke as education secretary starts here. “Why not?” she laughs. “If Andy Burnham wants to talk, he knows where I am.”