Ms Claudia Schiffer served him tea, and he has co-starred with Sir Michael Caine. Not bad for a 25-year-old lad from Aberystwyth.

In Kingsman: The Secret Service, the latest cinematic riot from Kick-Ass director Mr Matthew Vaughn, Mr Taron Egerton plays Eggsy, a promising youngster from the wrong side of the tracks who is recruited by the “Kingsmen”, an international intelligence agency operating out of a Savile Row tailor’s shop. With the help of veteran Kingsman agent Harry Hart, AKA Galahad, played by the ever-dapper Mr Colin Firth, Eggsy runs the gauntlet of the agency’s training programme: a spy equivalent of finishing school. It’s a rags-to-riches tale complete with gadgets, girls and a mega villain bent on world domination: think Connery-era Bond meets My Fair Lady.

Which raises the question: which version of his character will Mr Egerton turn out to be? On the Eliza Doolittle scale of rags to riches, which Eggsy is Egerton? The unrefined London street kid decked out in sweats, baseball cap and Nike Air Force 1s? Or is he Eggsy, AKA Lancelot, the newly qualified secret agent, softly spoken and smartly dressed in a Savile Row suit?

Well… neither, as it turns out. For starters, he’s not even from London. He’s Welsh. “Just a simple country boy,” as he puts it. “I’m definitely not that guy in the suit. But I’m no Eggsy, either. I just don’t have that urban edge.” Originally from the Wirral, just west of Liverpool, he moved with his family to the Welsh isle of Anglesey before relocating again at the age of 12 to Aberystwyth, a Victorian tourist town on the west coast of Wales. He still calls “Aber” home, and is heading back there, post-photoshoot, to celebrate his 25th birthday. But just to confuse things further, he’s spent the past five years pursuing his acting career in London. The resulting accent is from everywhere and nowhere: a twist of south, a dash of west and a little Welsh mixed in with an occasional, lilting Scouse inflection. Whatever he sounds like, it certainly isn’t Eggsy. Either of them.

“I listened to a lot of Plan B to get that voice right,” he says, citing rapper, actor, director and all-round Renaissance man Mr Ben Drew as the inspiration behind his foolproof impersonation of a London street kid. “I watched Ill Manors and Harry Brown. Watched a series called Top Boy, too. Watched a lot of those lads – Riz Ahmed, Noel Clarke, Adam Deacon, Ed Skrein.”

The men Mr Egerton has listed might not be household names, but they represent some of the best acting talent to have come off the streets of London in recent years. Mr Ahmed, who was born in Wembley and studied at Oxford university, recently starred opposite Mr Jake Gyllenhaal in Nightcrawler, while Mr Skrein, from Camden, became one of the few actors to have left the cast of Game of Thrones with his character’s head still on his shoulders when he quit the role of Daario Naharis to step into Mr Jason Statham’s shoes as the star of the new Transporter movies. A lot of them, Messrs Ahmed and Skrein included, also have links to the city’s underground grime scene – a musical genre that has played a crucial role in the development and dissemination of the contemporary London accent. In other words, Mr Egerton has done his homework.

And the results pass muster: severe enough to sound authentic, yet clear enough to be intelligible. “I stressed out over it so much,” he says. “I didn’t have a dialect coach. I was terrified of sounding like I was doing a bad impersonation of Ray Winstone.” It didn’t hurt that he’d just wrapped filming on The Smoke, a Sky 1 drama following the lives of a team of London firefighters.

Accents aside, this movie was a huge leap into the unknown for Mr Egerton, who only graduated from London’s Royal Academy of Dramatic Arts in 2012, having previously studied at Aberystwyth Arts Centre. Other than The Smoke, there have been a few stage roles – including one in a star-studded 2012 National Theatre production of The Last of The Haussmans – but nothing to compare with the scope of a major studio-backed movie such as Kingsman. He recalls rehearsals with Mr Colin Firth in a London pub, auditions at the director’s home – where he was served tea by Mr Vaughn’s wife, Ms Claudia Schiffer – and many other surreal moments.

Any particular highlights? “Meeting Samuel L Jackson is definitely up there,” he smiles. “But really, where do you want me to start? I met Michael Caine. Sir Michael Caine. He’s such an icon that you almost forget that he’s a real person. Mark [Strong] and Colin [Firth], too… they’re two actors that I’ve admired for years.” It was all rather a lot to take in for Mr Egerton, and despite already being in fantastic shape as the result of two months’ hard physical training, he often found himself hitting the gym in the evening as a way of letting off steam. “After a long day spent dispatching miscellaneous goons and sharing scenes with your childhood heroes, you need to find a way to clear your head.” Hanging out with Hollywood actors is just something he’ll have to get used to: next up is a role alongside Mr Tom Hardy in the Kray brothers movie, Legend.

Did Kingsman teach him anything about style? Well, for reference, he’s wearing a pair of Nike Air Force 1s today – but they’re not the blinding-white type that his character Eggsy wears. These have been worn in to the point that they’re just beginning to inhabit that sweet spot between box-fresh and falling apart, and they’re paired with a plain white tee and a pair of Lanvin sweatpants that he rather fell in love with during the shoot. He isn’t quite sure what to say when asked to define his own personal style, but he’s young, and has ample time to work it out. There is one piece of clothing, though – from the MR PORTER Kingsman collection, no less – that he admits a fondness for. “That blue number will always have a special place in my heart,” he says, pointing to the rail where the double-breasted, pinstripe suit that he wears throughout the film’s final act is hanging. “Not to spoil the plot, but I save the world in that suit.”

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