As a quiet teenager secretly writing songs in his bedroom, Dan Smith had no real intention of becoming a global star - but it's happened anyway and he still can't get his head around it, as Andy Welch discovers.
Bastille's debut Bad Blood was released in March of this year and promptly went to the top of the album charts.
It's the 10th best-selling album of the year so far. An impressive stat - even more so when you consider the only artists to sell more than these unknown Londoners include household names like Justin Timberlake, Daft Punk, Calvin Harris, Pink and Michael Buble.
Next month, Bad Blood will be released in the US, and "loads of other places", says their founder and reluctant frontman, Dan Smith.
"It's been an interesting year, definitely," he says with typical understatement.
"People ask me what I was expecting, and I have to say I don't really know. Maybe I'm incredibly naive, but I was just hoping we could keep touring and make a second album."
He didn't think Bastille's music would be heard outside the UK, let alone beyond Europe.
As we speak, though, he's making preparations to go to Japan for the Summer Sonic Festival, and as soon as that's done, there are a couple of UK festivals to play, before jetting off to the US for a full tour.
"It's mad, isn't it?" says 26-year-old Smith, who's still struggling to comprehend what's about to happen.
"Going to play in a country for the first time... It's one thing to win over a crowd when you're playing to them, but it's another to have them on your side before you've even turned up."
He's referring to Pompeii, the fourth single to be released from Bad Blood, and by far the most internationally successful.
"Everywhere we go people know it," he says. "It's so strange to think the song has got there before we have."
Smith began writing songs in his bedroom when he was either 15 or 16, he can't quite remember. He says they were "inaccessible, odd and not very good", and performing was far from his mind. He didn't even tell his friends he was songwriting; his family only knew because they could hear him through the wall.
"Getting up and performing on stage isn't at the top of a list of things I like doing, even now," he says. "It wasn't until I was at university and my friends were all in bands, and I started going to a lot more gigs, that I thought about it. It was because of a combination of seeing more live music and them gently encouraging me that I started playing live."
Back then, he was plain old Dan Smith, but a year or so later, in 2010, around the same time he met the three people now in the band, he came up with the Bastille moniker.
After designing a logo on his computer, he put a few of his early recordings online and the feedback was immediately positive.
"I don't know if I've ever really felt that something I'd written was a great song, but I know the feeling of writing a song and liking it," he says. "But yeah, people said they liked the songs and that's definitely when things started for us.
"Back then I liked the idea that no one knew whether it was a band or a solo project. From there it was all about waiting to see what happened, and what has happened is beyond my wildest dreams."
He says he has a patchwork approach to songwriting: recording snippets of different items before piecing it all together on his laptop. One thing that remains throughout is his ear for a huge chorus, although he can't force that element, he adds.
"I've always been obsessed with hooks and strong melodies. I mean, there's loads of amazing music that doesn't have that, but they're the songs you remember, aren't they? The ones that get you, the ones with a melody or some sort of hook.
"Saying that, that isn't something I can do consciously, and if I did, in my experience it just doesn't work. Or it will work but I'd always know the song came from a cynical place."
Pompeii and Things We Lost In The Fire definitely have that quality, and it's no surprise they've done so well around the world.
"With Pompeii, that was always going to be released around the time of the album coming out, but no one around us had any idea it was going to do as well as it has," he explains. "At the time, I definitely didn't think it was a hit.
"We had been playing it live for a year before it was released. Crowds liked it and it always went down well, but it wasn't changing people's lives, so we weren't prepared for it to do so well."
The reaction when they play their debut single Overjoyed live does raise a few eyebrows, though.
"Our crowds are generally quite vocal and up for it, so we're lucky, but during Overjoyed in Manchester recently, there were four circles of moshing," Smith explains. "It's a really depressing bit of music if I'm honest, so I never expected that.
"And at another gig, four people were carried out after fainting. Not that our gigs are horrific or dangerous, I should add, but we never thought people would dance 'til they dropped!"
Bastille will have to get used to seeing more of this. They have a full UK tour throughout October to prepare for and there are already plans for even bigger shows next year.
"You always hear that being in a band is an incredibly insecure existence, you never know what's happening in the next couple of months," says Smith. "I suppose we've just put our heads down and got on with it.
"When I was making songs in my bedroom I was never aiming for anything specific, and none of us are particularly ambitious when it comes to what we want, so that's why I feel so taken aback by all of this. It's quite a strange feeling, really."
Extra time - Bastille
:: Bastille are Dan Smith, Chris 'Woody' Wood, Kyle Simmons and Will Farquarson.
:: Smith took the name from Bastille Day, which takes place in France on July 14, the same day as his birthday.
:: They released their debut single Overjoyed in April 2012, five months after signing to Virgin Records.
:: Smith is a huge fan of the work of film-maker David Lynch. Their song Laura Palmer is named after the character in Lynch's cult TV series Twin Peaks.
:: The band recently remixed a song written by Lynch and went to his studio to meet him.
:: Bastille's current single Laura Palmer is out now. They soon begin a UK tour, full dates below.
9 - London, Cafe 1001
23 - Reading Festival
24 - Leeds Festival
1 - Jersey Live
5 - Bestival
7 - Bestival
7 - Bristol Colston Hall
8 - Yeovil Westlands
9 - Portsmouth Guildhall
10 - Norwich UEA
12 - Cambridge Corn Exchange
13 - Cardiff Great Hall
15 - London O2 Academy Brixton
16 - London O2 Academy Brixton
17 - Leicester O2 Academy
21 - Leeds O2 Academy
22 - Manchester Academy
23 - Sheffield O2 Academy
1 - Newcastle O2 Academy
2 - Nottingham Rock City
3 - Birmingham O2 Academy
4 - Southend Cliffs Pavillion