Taron Egerton is a lucky man and he knows it. The actor has come a long way since his breakaway performance in 2014’s Kingsman: The Secret Service, but in person he still carries a half-embarrassed, half-disbelieving edge that the life he’s leading right now is truly his own. Being catapulted from the RADA classroom to playing the lead in a cult hit will do that to you, I guess.

“I never know what to say!” Egerton scratches the back of his head and laughs sheepishly on more than one occasion in our interview, but he carries any unwanted interest in his life with a natural charisma that makes me ever so slightly hate him.

As Kingsman’s Eggsy Unwin, an east London accent and ballsy attitude make him an unconventional but lovable spy, but sat here on the sofa in a Chelsea photo studio, he’s a well-spoken Welsh bloke who you’d love to join for a few pints down the pub. He’d probably get the beers in as well, the generous bastard.

What character and actor have in common, though, is a restless energy and a way of taking everything in their stride – oh, and the occasional use of expletives. “Fucking hell, no… Sorry pardon my language!” Egerton covers his mouth in mock shock at the naughty word that tumbled out of it. I asked him if he ever expected to be in this position as a movie star – I mean, he’s good looking, clearly talented at his art, and had the springboard that is the Royal Academy of Dramatic Arts in his top pocket, surely he saw big movies in his future?

“No. I fell in love with theatre. That was really what I wanted to do – the live nature of it, the immediacy of being in front of an audience, the thrill of it,” Egerton tells me.

As a teen living in the Welsh village of Llanfairpwllgwyngyllgogerychwyrndrobwllllantysiliogogogoch (yeah, that one), Egerton grew up as part of a creative family. Dad a talented musician, Mum a hobbyist clothing designer, it was only a matter of time before Taron found his calling. At 15, his friends introduced him to the local youth theatre – and that was it.

“I really felt that achieving regular work and a career working in the great theatres in London was hugely unattainable, but it was a really respectable vocation and something that I really looked up to – and still do.”

True to his ambitions, Egerton bagged his RADA place “as a young 19 year old – too young, in hindsight”, before he landed his first big break in the form of signing with influential agent Lindy King in his final year. Before long, he made his debut not in his beloved West End, but on Sky One’s high-budget The Smoke, and then Matthew Vaughn’s Kingsman script landed on his desk. “I just read it and went, ‘Shit, I know what to do with that,’” Egerton says. “Not in an arrogant way, I just felt very, very strongly that I was the man to play the role.”

He didn’t know at the time that his co-stars would turn out to be Colin Firth, Samuel L Jackson and Sir Michael Caine – and, more importantly that the film would grow into a $420m smash hit – but his confidence was well placed. He was the man for the job, even beating out a then-unknown John Boyega to play Eggsy. (I think the Star Wars actor will have made peace with that disappointment by now.)

Vaughn took a calculated risk in casting Egerton, an untested young actor who hadn’t been on a film set, let alone played the lead. “It was a baptism of fire, really – straight in at the deep end,” the 28 year old says in the understatement of the century. “I remember very clearly thinking that I was going to get found out and that I was going to lose the job. There were all sorts of things which in retrospect seem absurd, and very personal insecurities, but I just was convinced that they were going to recast,” he laughingly admits.

Funnily enough, he was “never fazed” by the calibre of actors he was working with, he just wanted to match their performance. “It wasn’t a guaranteed success, but even from the very early stages – something about [director] Matthew, something about the script, the story, the design of everything, the cast – I was always confident that it was going to have something quite special about it.”

Behind the nervous excitement and the pressure Egerton piled on himself was something more. Whisper it quietly, Taron: “It sounds like a dirty word, ‘ambition’, but I’ve always felt quite ambitious. It was an incredible opportunity, and I just remember feeling very determined to do a good job.”

I read the Kingsman script and went, ‘Shit, I know what to do with that’

Let’s fast forward to 2017. Here we are sitting in the knowledge that Kingsman surpassed all expectations to become one of the biggest hits of 2014. As for Egerton, he took his scene-stealing performance into new roles alongside Kit Harington and Alicia Vikander in Testament of Youth, Tom Hardy in Legend, and an appearance as the titular Eddie the Eagle with Hugh Jackman supporting.

The actor’s stocks are still rising as we come full circle to Kingsman: The Golden Circle. “Yes, the difficult second album, as Matthew keeps calling it.” Egerton nods. If Kingsman had the benefit of surprise, Kingsman 2 carries the heavy weight of expectation. But is the film up to the challenge? Egerton nods. “In a way [the pressure] is very exciting. I think it galvanises everyone and makes everyone very focused, obviously no-one more than Matthew.”

Matthew Vaughn witnessed his last cinematic success Kick-Ass receive a, er, critical ass kicking for its sequel (Vaughn neither wrote or directed it), so his commitment to the Kingsman world is a sigh of relief for its huge following. This is a world Vaughn created, after all, and one Egerton is very happy to continue to inhabit.

“It was never guaranteed that Matthew would direct the sequel,” Egerton says. “But I think it’s very clear to see that he’s very much in love with the world of it – the process of making these films and the characters.”

If Layer Cake announced Vaughn’s directorial talents to the world, Kick-Ass was the British filmmaker’s opportunity to pen a script that threw two fingers in the air at the burgeoning superhero franchises and their tired clichés. It’s this irreverence that, Egerton thinks, lifelong spy movie fan Vaughn has brought to the secret agent genre.

“If you asked Matthew who his heroes are, one of the first people he’d say is David Niven [the Oscar-winning actor who played James Bond in the 1967 spy parody Casino Royale]. This whole thing is a love letter to the spy genre, albeit in a slightly warped, twisted way. Matthew is a cinephile: he knows what movies he likes, he knows the films that were formative in his growth as a filmmaker, and he likes to pay homage to them.”

So what can Egerton tell us of Kingsman 2? He smiles and rubs his hands together: “I saw the final piece for the first time a couple of months ago… It’s bloody good.” It’s a broad grin on his face now – he’s desperate to tell me the whole plot but keeps me hanging.

What we do know is the Kingsman is back – and this time it’s personal. Or at least that’s the particular trope Vaughn will be toying with. We see a lot of that in the tantalising trailer, set to the soundtrack of none other than Frank Sinatra. Egerton laughs when I bring up the song choice: “I remember Matthew calling me and saying, ‘I’m thinking of putting Frank Sinatra on the trailer.’ I went, ‘Which one?’ He said, ‘“My Way”,’ and I told him, ‘You’ve got to do it. You’ve got to do it!’”

It feels like a brave decision to expand the Kingsman world further – neatly summed up by Vaughn blowing up the Kingsman mansion and HQ in the trailer. “That was one thing that Matthew was very, very clear about, even when we were making the first one: that Kingsman would go up in smoke at the start of the second one, which kind of seemed a bit mad since that’s what the film is about, but I’ve learned not to question him, because he just knows what he’s doing. It’s great because it creates this huge vacuum – a real problem that needs to be addressed.”

What’s the solution? “Calling in the Yankee Doodles!” Egerton claps with the glee of somebody reading the script for the first time. The result is polarising the right-and-proper Britishness of the first film, still in abundance here in the second, with the Kingsman’s American cousins, the Statesmen, with their yee-haw exuberance, and bourbon-drinking, gun-slinging, lasso… lassoing agents. Oh, and there’s the small matter of villain Poppy, played by Julianne Moore, who grinds her enemies into burger meat. Chances are Eggsy’s going to have to save the world all over again – and, yes, that means there’ll also be a host of new spy gadgets, including a rocket-launcher suitcase, cologne-bottle grenade and a London black-cab submarine. Egerton’s nodding: “Yup, it’s bloody brilliant!”

The Americans in question are nothing to sniff at, of course. Jeff Bridges, Channing Tatum and Halle Berry all feature frequently in the sequel – all of whom, it transpires, were huge fans of the original. “What was amazing was how fanboyish they were about the first one. It was like, ‘What do you mean you loved the first?’” Egerton shakes his head. “These guys, Jeff Bridges especially, I admire so much. Channing and I got on really well, but it was great that they all brought an energy to the film that was a bit different to the first.”

But it’s still Egerton who’s the star. His laughter is contagious, his nervous energy – bouncing foot, shifting around in his seat, fiddling with his cap, et al – is engaging, while his tendency to self deprecate a sign that Hollywood hasn’t stolen his sense of real-world perspective. It adds up to a guy who talks about the industry like he’s still on the outside of it – and, more importantly, when Egerton tells you he’s excited about Kingsman: The Golden Circle, it’s genuine. Or he’s a bloody good actor. Maybe both.

“If you didn’t like the last one, for whatever reason…” he shrugs his shoulders and pulls a face. “Apologies, because you’re not going to like this one. But it really is terrific. The characters are so colourful and larger than life, and the action is relentless. One thing that you won’t hear people talk about a lot is the heart of it. It’s actually, I think, quite moving in places, particularly with regards to my relationship with Oscar-winning Mr Firth.”

For those who haven’t seen the first film, the death of Firth’s character Harry Hart, code-named Galahad, is the film’s biggest shock. But, despite being shot at point-blank range Harry is, miraculously, back from the dead and plays a major role in Kingsman 2.

“In terms of how he’s back, I can’t reveal anything more than he is back, there’s an eye patch going on, and we spent a lot of time working together in the film,” Egerton eyes the room as if looking for any secret cameras catching him out – a by-product of playing a spy, I guess. “Obviously the heart of the first one is in that relationship between those two characters, and the fact that Harry becomes a father figure to Eggsy. It was genuinely sad when he went in the first one. Now to think we could have him back – although who knows how – is just so exciting.”

It takes a lot to squeeze me into a suit – I mean, fucking hell, life’s just a bit too short for that, isn’t it?

Aside from the excitement at seeing Kingsman’s particular brand of frenetic violence and unashamedly pulpy satire again, it’s an opportunity to see the likes of Egerton don a tux like only an agent of espionage can. “As you can see, I’m an impostor,” the jersey shorts and plain tee Egerton points to are finished with a baseball cap fixed to his head.

“Really, it takes a lot to squeeze me into a suit – I mean, I absolutely love to put one on, but day-to-day, fucking hell, life’s just a bit too short for that, isn’t it?”

Still, the look is surely the perfect audition for another spy… “Ah man, there are so many guys who would be better for Bond right now.” The corner of Egerton’s mouth creases, and he seems to mull that one over a little more. “It is 007, though. You never know. Ten years of wear on my face, I might be ready!”

As interesting as an Egerton casting could be for the world’s most famous spy, two such similar roles wouldn’t sit easily into the young actor’s varied CV. “I’m quite wary of falling into the trap of doing heroic lead parts, because, as fun as they are, I think it can be a bit pigeonhole-y, but Robin Hood, I think the reason I was very drawn to that was because there’s something very human about it.”

Egerton’s talking about his next major project that wrapped at the end of summer – and it’s another indicator that he’s transitioned from flying below the radar into a serious Hollywood prospect.

One-time Peaky Blinders director Otto Bathurst heads this new take on the fabled tale, with Egerton drawing the bow and arrow as the film’s title character.

“I think we’ve tried to dispel any of the overly mythic elements of Robin Hood. It’s supposed to be a kind of grittier – albeit funny – version of the story, with Rob being more three-dimensional and rounded, as opposed to this archaic tapestry.” There’ll be the elements of darkness and modernity that typify Peaky Blinders’ portrayal of 1920s post-war Britain, too, this time applied to a 15th-century setting. “It’s set at the time that Robin Hood would have lived, but it has elements of modernity in terms of design, aesthetic style, dress, weaponry and industry.”

With an interesting cast list including Jamie Foxx as Little John and comedian Tim Minchin as Friar Tuck, Egerton hopes that his next step will continue his run of box office successes, but is he conscious of plotting his way through his career, choosing directors and scripts only at the right moment?

“I don’t think I’m overly analytical or planned about the choices I make, other than the fact that I very consciously like to try and frighten myself and do things that are different.” He pauses, and feels the need to add to his answer. “I don’t know, it’s not always that simple, though. With Robin Hood I’m not sure I felt frightened about doing it. I definitely did with Eddie the Eagle. I quite like the idea of doing things to sort of surprise myself, and flex different muscles.” He sits back on the sofa, content for a moment, but before he’s settled he’s leaning forward again: “I just think… Ah, I’m really hesitant to describe myself as an artist, but I think when you’re creating something, you’re never better than when you feel slightly out of your comfort zone.”

I like the idea that I could play someone who’s a bit of a shit

From our chat, it sounds like Egerton is getting uneasy at playing naturally likable characters. “I suppose, without being needlessly calculated about it, I like the idea that I could play someone who’s a bit of a shit.”

I suspect that his role in the upcoming Billionaire Boys Club remake – alongside Kevin Spacey, Jeremy Irvine and Ansel Elgort – will begin to explore that theme. As scammer and rich kid Dean Karny, it’ll be interesting to see an unlikable Egerton, because the one sitting in front of me is far from it.

I can see why Firth said last year: “I keep trying to figure out if he knows, or cares, how talented he is. I could spend hours in his company, trying to cultivate some flaws in him.” Good luck, Colin. Egerton is on a roll: “I’m hungry to have a go at anything that I think I can do.” There’s that boyish grin again. If his appetite for new roles is even half of Hollywood’s desire to cast him, we’re going to be seeing an awful lot more of Egerton in the years to come.

Kingsman: The Golden Circle is in cinemas now. View the trailer below: