They’re already the BBC’s darlings and favourites of DJ Annie Mac – and with their biggest ever gig fast approaching at Chalk Farm’s The Roundhouse, Half Moon Run are teetering on the edge of mainstream success.

What’s more, the Canadian four-piece have sold out four consecutive homecoming shows in Montreal at the city’s biggest indoor venue.

They’ll play the gigs after they finish their mostly sold-out six-week tour of Europe promoting their second album, The Sun Leads Me On – a more mellow continuation of the folk-influenced, harmonic indie rock of their debut, Dark Eyes.

The group admit that though they’ve worked hard – touring or recording almost non-stop since they formed in 2010 – they’ve also been lucky. “We have a ‘yes’ policy to everything, we take every opportunity,” explains multi-instrumentalist Dylan Phillips, who plays drums and keyboards.

After meeting through a Craigslist advert online in 2010, and clicking instantly, they fell into a recording contract after helping some friends who had contacts in the industry. A label executive heard their music, and instantly signed them – without the band even looking for a contract.

Despite not forming as friends, the group are now a tight-knit unit – which perhaps is why their sound is equally cohesive.

“There was an article published a few years ago that said we weren’t friends,” says Phillips. “It’s just that we didn’t know each other when we started and didn’t spend much time talking about anything else but music to each other, and apparently that meant we hated each other. But we’ve now been on the road together for several years and we’ve become very close.”

Their passion for their craft is clear. All four members – Phillips, Devon Portielje, Isaac Symonds and Conner Molander – sing and play a number of different instruments. More unusually – they do it well.

But before the band recruited Symonds and became a four-piece after their Dark Eyes tour, this was sometimes a curse during live performances.

“I would drum parts but only have one hand to do it, as I was playing keyboards with the other,” says Phillips. “Isaac was already our friend and we said, let’s give it a shot to beef up our live shows. It didn’t take long until he was a fully, creative member of the band.”

It’s hard to stand out in the indie-rock genre, but the group’s folk-infused harmonies, accomplished musicianship, and melodic tunes are clearly winning over fans.

Critics often liken their sound to Fleet Foxes, but the comparison bemuses Phillips. “One of the main reasons that point is made is because we sing in harmony. I don’t think ‘harmony’ is a genre. It’s something that exists in all music. A lot of bands don’t sing as much harmony so when it’s a band plus harmony, that equals Fleet Foxes. But our style of music is very different, I think. I love Fleet Foxes but I think that’s why we get that comparison.” But being likened to an indie success like Fleet Foxes – even if that comparison is not wholly accurate – surely signals that arena gigs are just around the corner?

Phillips is modest. “I don’t think you can ever expect things to go one way or the other. The most important for us is to focus on having a good show and writing good music. If people like it and we sell tickets, that’s great, and if people don’t like it, and don’t buy the album, that’s the way it goes.”

Wembley may be calling one day, but for now it’s The Roundhouse, and for this humble band, that’s more than good enough for them.

Half Moon Run play The Roundhouse on March 23.