Half Moon Run was one of those bands that seemed to arrive fully formed. With their 2012 debut, Dark Days, and its 2015 follow-up, Sun Leads Me On, the Montreal quartet effortlessly fused indie-folk intimacy with art-rock ambition, yielding a sound coloured by heart-racing guitar melodies, clattering percussion, and gorgeous, CSNY-worthy four-part harmonies. But as multi-instrumentalist Conner Molander tells Apple Music, “As soon as something becomes a convention, the proper thing to do is to just flip it on its head. People can tell if you're doing something that's been rehearsed a million times.” However, for Half Moon Run, finding that new direction would take the better part of four years. “We're not the fastest writers,” Molander admits. “We took a long time writing and then we took a lot of time recording, too—some of the songs we did over, like, four times. Looking for the right kind of sonic fingerprint can be tricky. We were just searching for it, but didn't know exactly what we were searching for until the end.” Compounding that sense of indecision was the fact that the world around them—in both the micro and macro senses—was entering a period of huge instability. “Everybody says it's a weird time to be living in,” Molander says, “but it's weird on a number of levels: politically, environmentally, and musically, too. When we first got into this in 2010-11, there was a lot of people we knew in what you would call the indie scene, and now I'm not even sure what's going on in the scene anymore. So we were looking for new musical influences. Me and [bandmate] Dylan [Phillips] both play classical piano, so we were trying to brush up on our chops and think of some new harmonic ideas.” That exploratory instinct pays off with A Blemish in the Great Light, an album that manages to fine-tune Half Moon Run’s songcraft while nudging the band out of their misty-mountain comfort zone. The dreamy night-sky expanse of previous records has given way to punchier, in-your-face productions: Opener “Then Again” may begin on traditional acoustic footing, with frontman Devon Portielje introducing a gentle, wistful melody, but over the next three minutes it gradually builds toward an intense, pedal-stomping climax. It’s the first of many sonic surprises in store here: “Favourite Boy” tops a smooth Fleetwood Mac groove with glistening Cure guitar lines to arrive at a sound that can only be described as yacht-goth; “Razorblade” weaves an eco-parable over the course a seven-minute, multi-sectional epic. But even the songs built from Half Moon Run’s familiar folk-rock toolkit offer startling moments: When the band locks into the crystalline chorus of “Black Diamond” (not a Kiss cover), it’s like a drive down a dark country road that’s suddenly illuminated by the blinding high beams of an oncoming vehicle. “That's something that's always been pretty instinctive, ever since the very first jam,” Molander says. “When we get to a certain point in the arrangement, we’ll throw on a harmony for emphasis or colour, and it just has this really special kind of utility to it that can lift the song up. I love that about our band.”