“I wasn’t taken seriously for a long time”: Mia McKenna-Bruce on life lessons from motherhood, cosy crime and working with acting royalty

Anyone who saw Molly Manning Walker’s 2023 coming-of-age film How To Have Sex came away with the same conclusion: the lead actor, Mia McKenna-Bruce, is a star in the making. As Tara, a teenager on her first girls’ holiday in Malia with her two best friends, her energy leapt off the screen. Her presence was magnetic, and her ability to express a conveyor belt of emotions in one look was captivating. Its themes around consent, growing up and teenage angst struck a chord with women everywhere – it’s no wonder it won her the Bafta rising star award.

“If I could go back and do it again, I would,” says McKenna-Bruce. “It was the most incredible experience because [its success] was totally something we didn’t expect. Molly really believed in me, and that gave me so much confidence as an actor.”

Now, her star continues to rise as she takes on the world of Agatha Christie as Lady Eileen ‘Bundle’ Brent in Netflix’s The Seven Dials Mystery. In the three-part series, written by Broadchurch creator Chris Chibnall, a practical joke at a lavish party ends murderously wrong, and it’s up to the inquisitive and determined Bundle to unravel the chilling plot.

On the face of it, it’s quite the gear-change from her last role, but McKenna-Bruce found she related to both characters in a similar way. “It was kind of nerve-racking [to figure] out what I was going to do next,” she says of the time following How To Have Sex. She wanted to find “a character who resonated with me” but also “mattered” and “said something”. Bundle, it turns out, was just that.

With filming for the upcoming Beatles four-film biopic also underway – she’s playing the wife of Ringo Starr, Maureen Starkey, opposite Barry Keoghan – and a two-year-old son, Leo, at home, McKenna-Bruce is in demand. Stylist sat down with the actor to discuss the pull of cosy crime, working alongside acting royalty and the life lessons motherhood has taught her.

The Seven Dials Mystery was written by Agatha Christie nearly a hundred years ago, but watching this adaption feels like new life has been breathed into it. How did you go about that?

I initially thought that was Chris Chibnall’s writing, which it is to a large degree, as the way he writes resonates with everybody. But then I read the book, and I realised the way Agatha writes Bundle feels very modern and ahead of her time. Supposedly, Bundle is based on Agatha herself, and from what we know of her, she was quite adventurous and free-spirited.

It’s perfect cosy January viewing. Do you think that’s all we can cope with right now, when life is so stressful?

Escapism in any form is what I want to see, and cosy crime is definitely for this time of year. I think right now is a time when we want to come together, and there’s not a lot out there that you can sit and watch as a family, but this you can.

It’s written by Broadchurch creator Chris Chibnall – did that influence your decision to take part?

Yes. I loved Broadchurch, so I thought, “I want to read this.” Then I met him, and he’s everything you could dream of and more. In our first read-through, he said, “Have fun while you’re making this, because if we’re not having fun, why are we doing it?” He set that precedent, and it was so much fun – I had the time of my life. Getting to be part of an Agatha Christie is the dream.

What do you think sets this apart from other Agatha Christie stories?

First of all, it’s led by Bundle, who’s young, full of love and life and has this fearless energy, which is something we haven’t seen a huge amount of. Secondly, with whodunnits, it’s easy to get excited by the clues and trying to figure out the answer, but it was important to us to always come back to “Why are we doing this?” Bundle has suffered a huge amount of loss, and it’s about what that does to a person. Getting to do that in the world of Agatha Christie is special – it has so much humour, but also holds onto the heart.

Did you find any similarities between yourself and Bundle?

I think so. It’s maybe not for me to say, but people have commented on it. What I love about her is her love for other people and her ability to connect with others – that’s what I aim to have. But in my first audition, I thought I’d ruined it. I’d just had a baby, I was in the middle of press for How To Have Sex, which was chaotic, I hadn’t slept, so I didn’t know any of the lines, and I was a complete mess. I saw one of the producers at an event that night, and she said, “We loved what you did earlier.” I said she must have been thinking of someone else, and she said, “No, you are the essence of Bundle.”

Women in that time were so often told ‘no’. Was it fun to play into that idea of ignoring the men who tried to shut Bundle out of the room?

Absolutely. Particularly in the 1920s, we know that women were pigeon-holed and getting to go against that idea was exciting. It led on nicely from doing How To Have Sex – I wanted to tell female-driven stories and play strong females, and that’s Bundle.

She’s often underestimated, especially by men. Is that something you’ve experienced?

Definitely. I think, as a woman, most of us have experienced that, but I’m someone who looks quite young for my age, so I wasn’t taken seriously for a long time. Having a baby was a huge learning curve in advocating for myself and my child – that helped in taking on this role of Bundle, who cares about something enough to not allow anyone to say no. I feel lucky that the timing of it was post having a child and experiencing what it feels like to be the one to have to speak out.

Helena Bonham-Carter plays Lady Caterham, Bundle’s mother, in the series. What was working alongside her like?

We’re the same person in a lot of ways; we have similar energies. I think Helena saw a lot of herself in me and took me under her wing. We had this beautiful sisterly relationship. Even though she takes the work seriously, she doesn’t take herself seriously. She has so much fun and getting to see someone who’s been working for such a long time still have that love and care about what they’re doing – I’m in complete awe of her.

Before we started the shoot, she wanted to go and be in the house so she knew what her home felt like as Lady Caterham. I’d be scared to ask for that, but seeing her do it and everyone say, “Yes, that’s a great idea,” taught me not to be afraid to ask for what I need.

Your sister ended up playing your body double. How did that come about?

Halfway through filming, I tripped on a carpet on set and broke my foot. We still had a lot to shoot, and the producers asked if, by any chance, I had a secret twin. People often think my sister, Ellis, and I are twins, so she came up the next day and played my body double until the end of the shoot.

It was so fun to have her on set, and I was proud that she got to see me at work. She’s a make-up artist, so she understands sets, but she got to experience the nerves and pressure that come with being in front of the camera. She’s said she appreciates that more now, and it’s made us closer. I’m so proud of her – she was so nervous, but by the end of the six weeks I thought, “Damn, she’s going to come for my job!”

You got married while shooting…

Yes, I don’t do things by halves! Apparently, I thrive off chaos. It’s like, what else can we throw in there? A wedding, a hen do, a broken foot, a seven-month-old baby. I couldn’t function without my family and friends keeping my brain in check.

What life lessons has motherhood taught you?

That being selfish isn’t necessarily a bad thing. That was my biggest fear for a long time, people thinking I was putting myself first, but actually, in being a mum, you have to prioritise your time and say no to things to be there for your child. I’ve learned to take better care of myself. Even little things, like making sure Leo drinks water – if I’m telling him to drink water, I need to drink water.

What’s your dream Sunday?

I’d go for a nice brunch, get some avocado situation and a coffee, then go for a walk, a good couple hours just strolling – one of those where it’s cold but the sun is shining. Then I’d come home, watch a good old movie like Chitty Chitty Bang Bang or Oliver Twist and do all the things you don’t have time to do, particularly as a mum, throughout the rest of the week: moisturise, shower, wash my hair.

You’re starring as Maureen Starkey in Sam Mendes’s upcoming Beatles biopic. How are you dealing with the pressure that comes with being involved in such a globally anticipated cinematic moment? And, equally importantly, what’s Barry Keoghan like?

It’s mental. When we started, I thought, “I’m way out of my depth.” To get to be involved in telling this story… it’s a proper ‘pinch me’. I have to accept that I’m going to feel imposter syndrome – look at what we’re doing! But that’s OK – when I tell myself not to feel like that, that’s when I spiral. I have to trust that the people who’ve chosen me to be there have done that for a reason.

But Barry’s an absolute dreamboat, I adore him. We’ve got such a beautiful story to tell together that we both really care about. The way he works, I don’t have to do anything; I’m just watching him do his thing. All of them [Harris Dickinson is playing John Lennon, Paul Mescal is Paul McCartney, Joseph Quinn is George Harrison] have thrown themselves into these characters, more than anything I’ve ever seen.

Finally, what are you most excited about for the future?

I’m excited that we’re stepping into the year of the horse in 2026. It means everyone is stepping into their power, and the work you’ve been putting in over the past couple of years is coming into fruition.

I started out as a dancer, and I always thought it was going to go that way for me, so I’d love to get the chance to do something that combines my love of acting and dancing. If I got a job that meant I had to do dance training intensely for six months, that would be dreamy.

Images: Matt Moorhouse; Netflix