Mia McKenna Bruce has revealed she broke her foot on the staircase at Badminton House while filming Netflix‘s Agatha Christie adaptation Seven Dials. 

The rising star, 28, puts on her detective hat in the role of Lady Eileen ‘Bundle’ Brent, as she sets out to solve an enigmatic murder. 

However, while filming the upcoming mystery drama, Mia broke her right foot stumbling down the ‘lethal’ staircase at the country estate in Gloucestershire.

‘As soon as I walked into Badminton, I thought that floor was over-polished,’ co-star Helena Bonham Carter told Daily Mail’s Richen Eden during an event at the British Library in London.

She claimed the Duke of Beaufort, who owns the house, above, doesn’t even use the staircase because it’s so dangerous.

And Harry Potter star Helena, 59, revealed she also slipped. ‘The staircase attacked us. They are lethal,’ she added.

Mia McKenna Bruce has revealed she broke her foot on the staircase at Badminton House while filming Netflix’s Agatha Christie adaptation Seven Dials

The rising star, 28, puts on her detective hat in the role of Lady Eileen ‘Bundle’ Brent, as she sets out to solve an enigmatic murder

However, while filming the upcoming mystery drama, Mia broke her right foot stumbling down the ‘lethal’ staircase at the country estate in Gloucestershire

The duke declined to comment when contacted by the Daily Mail. 

It comes as the cast put on a glamorous display at the premiere of the new series on Thursday.

Stepping out for the premiere, Helena, 59, showed off her ageless beauty.

Helena wore a black and pink floral lace midi-dress in a sheer tulle fabric, which featured a bejewelled belt, high neckline and a tiered skirt.

She paired the dress with chunky black, tan and white patent loafers, with her dark locks in tight curls and a bright red lipstick.

Meanwhile How To Have Sex star Mia, who won the EE BAFTA Rising Star Award in 2024, looked sensational in a black velvet figure hugging gown.

The strapless gown featured a lace lining at the bodice and ruched fabric, with the actress pairing it with a feather boa shawl.

Mia posed for snaps on the red carpet with Queen Charlotte: A Bridgerton Story star Corey Mylchreest, who plays Gerry Wade in the Netflix Agatha Christie adaptation.It comes as the cast put on a glamorous display at the premiere of the new series on Thursday.

It comes as the cast put on a glamorous display at the premiere of the new series on Thursday (pictured Helena and Mia)

Mia posed for snaps on the red carpet with Queen Charlotte: A Bridgerton Story star Corey Mylchreest, who plays Gerry Wade in the Netflix Agatha Christie adaptation

All three episodes of Agatha Christie’s Seven Dials are set to land on Netflix on Thursday, January 15

Also in attendance was Sherlock star Martin, who plays Superintendent Battle

Edward Bluemel, who also stars in the series as Jimmy Thesiger, wore a striking navy cape coat over a pale blue shirt and black trousers

Corey opted for an all-black ensemble, featuring a tailored blazer with a t-shirt and high-waisted pants, as he sported a full beard.

Also in attendance was Sherlock star Martin, who plays Superintendent Battle.

Martin looked dapper in a navy pinstripe double breasted suit, paired with a patterned tie and brown suede loafers.

Edward Bluemel, who also stars in the series as Jimmy Thesiger, wore a striking navy cape coat over a pale blue shirt and black trousers.

The trailer begins at a masquerade ball in the mid-1920s, where the handsome Gerry Wade is seen flirting and dancing with Bundle, before being interrupted right as it seems he is about to propose.

However, the next morning the household are disturbed by the noise of a cacophony of alarm clocks from Gerry’s room, sparking the ire of Lady Caterham.

A shocked and devastated Bundle investigates only to find her future fiancé lying dead in his bed, with seven clocks arranged on his mantelpiece.

Channelling her grief and despair into vengeance, she vows to uncover who is responsible for Gerry’s death, telling her mother: ‘I’m not going to rest until I find out what happened to him’.

The gripping three-part seires is an adaptation of Agatha Christie’s 1929 novel 

But as she begins to delve into the mystery of ‘the Seven Dials’, she received repeated warnings to stay away by her friends Ronnie Devereux and Jimmy Thesiger, as well as Battle, a Scotland Yard superintendent looking into the case.

Ronnie warns: ‘Be careful who you speak to about this’, as Battle echoes: ‘This is treacherous with a high degree of peril.’

But ignoring their warnings, Bundle is seen stubborn continuing her investigation to get ‘the full picture’ while Lady Caterham insists: ‘People who go looking for trouble usually find it’.

And the trailer shows that trouble is indeed brewing, as scenes flash of someone being shot, a masked figure, Bundle weeping over a bloodied body and then falling from a window.

However, she proclaims she will keep going until she finds out who murdered Gerry, vowing: ‘I am not going to stop until I get to the truth’.

The timeless mystery has been reimagined for a modern audience by Broadchurch creator Chris Chibnall and is directed and executive produced by Chris Sweeney.

Speaking about the ways they’ve adapted it, Mia told Tudum: ‘It was really important to make Agatha Christie feel accessible to people who hadn’t read her work but also hold on to the heart of those murder mysteries. I really feel like we did what we set out to do.’

While she explained how her character, Bundle, also behaves differently to how upper-class women were expected to in the 1920s.

All three episodes of Agatha Christie’s Seven Dials are set to land on Netflix on Thursday, January 15.

It marks the latest adaptation of one of the Queen of Crime’s novels for the small screen, following a slew of versions by the BBC, including Witness For The Prosecution, And Then There Were None and last year’s Towards Zero.