King Charles III: Charlotte Riley on playing a scheming Duchess of Cambridge

Actress discusses the BBC's controversial King Charles III, Peaky Blinders, and the 'masochistic' creative industries

The actress Charlotte Riley as Kate Middleton in the BBC's 'King Charles 111'

Who knew Kate Middleton, the fashion-plate cypher and consort, had such hidden depths? That the Home Counties girl-next-door who married her prince was in fact a steely Lady Macbeth, goading her weakling husband, Prince William, to seize the throne from his father, Charles?

That anyway is the premise of King Charles III, Mike Bartlett's hit stage play now preserved as a BBC TV drama. Much to the discomfort of many viewers, no doubt, this future-fantasy begins with the funeral of Queen Elizabeth II, her ageing heir rapidly fomenting a constitutional crisis when he refuses to put his signature to a piece of legislation limiting the freedom of the press.

With the House of Windsor dithering and in danger of being abolished, the Duchess of Cambridge emerges as a political force, scheming a solution that would see the royal family skip a generation, ditching the troublesome Charles and saving its skin.

“I see her as pragmatic rather than ruthless,” says Charlotte Riley, who plays Kate. “Her business brain understands that the royal family must remain relevant.”

Like Kate, Riley was joining a well-established family – in her case a cast that had travelled with Bartlett's original stage play from the Almeida Theatre in London to the West End and Broadway.

Tim Pigott-Smith as Charles, Margot Leicester as Camilla, Oliver Chris as Prince William and Richard Goulding as Prince Harry have been honing and polishing their roles since 2014. “Kate was new to the family and I was new to the family,” says Riley, who took over the part from Lydia Wilson. “But they made me feel so welcome so quickly that I didn't feel like an outsider for too long.

“It was great because they had such a huge well of knowledge from working on the piece for three years that it meant that I then inherited all the solutions that they'd worked through. They took me under their wing and got me up to speed so I was running with them as quickly as possible... Ollie [Oliver Chris], for example, met up with me and read scenes with me before the rehearsals.”

The firm: Tim Pigott-Smith plays Charles and Charlotte Riley plays Kate Middleton (BBC)

Pigott-Smith was as helpful as the younger cast members, and Riley was understandably shocked by his death last month at the age of 70. “I hadn't known him that long... only since last October... and those guys had spent three years on stage with him”, she says. “But he had a massive impact on my life. Since his passing many other actors have talked to me and everybody says the same thing – what amazing counsel he gave them. Being the lead actor in something, you're incredibly busy and incredibly tired, but he always found time to talk to me and other new members of the cast.

“And I was coming to this piece as a new parent... it was my first job away from being a full-time parent... and he offered some really wonderful, thoughtful anecdotes about his experience of being an actor and a parent. I know it's bizarre, but I'm just so pleased that that performance was captured on screen – it will be very bitter-sweet when it's aired but, I mean, could you ask for a better homage to his career?

Bartlett wrote his play in blank verse, which, says Riley, lends a Shakespearean tone to the drama. “I was a bit daunted by it but then you quite quickly leave it behind so you're not labouring the text, and the text does the work for you. It was quite weird watching it back because you do forget after a few moments that it's verse, it just feels quite natural.”

The Duchess of Cambridge has only ever conducted a handful of on-the-record interviews, so Riley spent endless hours “going down a YouTube wormhole”, seeking out postings by members of the public who had met Kate and managed to record her speaking more informally. “I really enjoyed watching those candid little moments that people have captured on their own phones,” she says.

“To see those tiny little beats where she's having an intimate conversation with somebody, I found them quite useful. But then you have to leave it behind and dive into Mike's world and get on with the text as opposed to trying to do any kind of impression of Kate. Because this is a parallel universe, isn't it?”

Riley with her husband, the actor Tom Hardy (Getty Images)

For Riley, it is indeed. She was born just 10 days before the Duchess, in 1981, but at the other end of England – near Middlesbrough, the youngest daughter (“the little accident that came along”, she has said) of an engineer and a nurse. After studying linguistics at Durham University, she went to drama school in London, receiving almost instant recognition when she played Catherine Earnshaw in Peter Bowker's ITV adaptation of Wuthering Heights. Heathcliff was played by a certain Tom Hardy, and the rest is history, the couple eventually marrying in 2014, and (another resemblance between Riley and the Duchess of Cambridge) giving birth to a child at the same time as Kate was securing the succession with Prince George.

She's a cheerful and friendly interviewee, quick to lob back questions of her own. She asks me about visiting film sets as part of my job (“boring, isn't it”) and the nature of class (“Is being classy other than being high class?”), and when I express an interest in her unusual Kurt Geiger shoes (“comfy is what they are”), wants to to know where I go clothes shopping (too boring to relate here). She also has a Teesside accent and is bemused as to why she is so often cast as the “posh bird” - most recently in Stephen Poliakoff's Close to the Enemy and BBC1's Jonathan Strange & Mr Norrell.

“Yeah... bizarre... very bizarre... not entirely sure why”, she says, adding that she has never used her natural accent on film. Except that is about to change, as she joins Rob Brydon, Daniel Mays and Jim Carter in a new film about a male synchronised swimming team, Swimming with Men, directed by Oliver Parker (St Trinians, Dad's Army). “Olly said 'I'd like you to use your own accent' and I nearly fainted”, she says. “We did the read-through only yesterday and it was really weird hearing a character in my own voice - to the point where I have to go home now and actually work on this because it's so bizarre to me now... it just sounded odd.”

Then it's back to the “posh bird” roles when, this summer, Riley reprises her wealthy, racehorse-owning widow May Carleton in Peaky Blinders, another project that has co-starred her husband. With three Christopher Nolan movies as well as The Revenant (for which he was nominated for an Oscar), Mad Max, Bronson and Legend (in which he played both of the Kray twins) to his name, Tom Hardy has a far more high-profile career. But does it irk her that in most newspaper articles she is generally introduced as “Tom Hardy's wife”?

Riley plays May Carleton in 'Peaky Blinders'

“I know what you mean but not really”, she says. “It is a fact that he is my partner and I think that's just another fact along with my age and where I'm from, and if an article is about me, it's just part and parcel of it.” Far more bothersome, she believes, is the lack of adequate childcare in the movie business. In fact Riley acts as ambassador for a pressure group called Raising Films, which aims to make film sets more parent and family friendly.

“Our industry can be quite masochistic”, she says. “Goldman Sachs have got their proverbial shit together about providing child-care and making sure people are seen as family members as well as employees, and I think we need a bit more of that in our industry. Given that we're a creative, artistic industry we should be way ahead of the game and we're falling so far behind.”

One of their initiatives, Ready Set Play, is to provide on-set childcare. “There are large double-decker buses which kind of extend into an on-set nursery that moves with location”, she says. “It's a fully Ofsted-checked, proper educational nursery... it's not a crèche.

“The point is, so many talented skilled women just completely drop out of the industry once they've had children because it's just nigh on impossible to get back in again. Seventy-nine per cent of people who became parents said it negatively affected their careers in the industry. That stands for itself doesn't it?”

'King Charles III' is on BBC Two on 10 May at 9pm and is available on digital download and DVD from 15 May