With their dark, anguished lyrics and indelible pop choruses, US emo-pop act Twenty One Pilots are perfectly pitched to be the latest darlings of sensitive teens the world over.
Although they are yet to become household names, the band's star is very much in the ascendant. In what has become a familiar narrative over the last decade, the Columbus, Ohio duo - singer, songwriter and multi-instrumentalist Tyler Joseph and drummer Josh Dun - built a huge, young fanbase on the back of a heavy touring schedule, self-released music and adroit use of social media, until a bidding war saw them sign to a subsidiary of Warner Records.
Already making waves in the States, this year has seen Europe take notice too, and eight months after their Belfast debut before a delirious teenage crowd at the 300-capacity Oh Yeah Centre, they're on their way back to play the Mandela Hall. Capacity this time? A whopping one thousand.
"When you start out at ground level, the idea is to progress and move on to bigger and better things," says the ambitious Dun. "I think it's kind of a goal for everybody to play the bigger room or the venue down the street with the bigger capacity. Not every band gets to do that. We challenge ourselves. We'll go into a venue and play the small room, and look at each other and say, 'Some day soon we're going to come back and play the bigger room'. So coming back to Belfast again and playing in a bigger venue, it's such a rewarding feeling."
Dun has fond memories of the last visit, including going back to the same restaurant for a second time in one day because the food was so good - clearly, restaurant critics aren't the only ones impressed by our culinary scene. But Dun says his family are even more excited about his visit to Belfast - because of their hair colour.
"People ask me all the time if I'm from around there because I have two totally redheaded sisters," he laughs. "They've actually won awards at festivals for their red hair! They always wanted to go and when they heard I was going to Belfast they wanted to come visit. They're pretty jealous about it!"
Twenty One Pilots' music is an idiosyncratic blend of styles that they call 'schizoid-pop', taking in the nerdy white hip-hop of Why?, the lung-bursting synth-pop choruses of Calvin Harris and the sensitive, emo-tinged lyrics of Fall Out Boy or My Chemical Romance. Joseph is a fidgety, intense performer whose songs address self-harm (Guns For Hands), parent-child relationships (House Of Gold) and even suicide (Truce). One recent YouTube comment below the video of the latter song sums up what the band means to many of their young fans. It reads simply: "I'm still alive because of them."
"It's crazy how invested some people are in the songs and the lyrics and the entire thing," says Dun. "It's very important and Tyler and I both take it very seriously. But at the same time, as much as people will come up to us and say that this song has helped them in some way or even saved their life, which is always crazy to hear, it's also helped me and saved my life.
"At the end of the day, the most comforting thing for me to know is that with this crazy thing, we're really all trying to figure it out. We're all together in that and maybe you're not alone with these dark thoughts - depression and even heavier things than that. I realise that I'm not alone. I'm trying to discover my purpose in life."