FTIsland don’t get enough credit for being as enduring a force as they are. Sure, they’re not the five-member powerhouse they once were, but with over fourteen years of idol life behind them, they’re one of K-pop’s longest-running groups. With age comes the threat of monotony. How does a band in their fifteenth year keep their sound fresh? New single Unthinkable (말이안돼) doesn’t answer that question, but it’s a solid rock ballad that’s sure to please fans.

Interestingly, this song was composed by a team of Western songwriters rather than the band itself. You’d think this would blunt the power of its sentiment, but vocalist Lee Hongki has a way of fueling even the most generic material with his expressive voice. FTIsland can rock with the best of them, but I’ve always loved their ballads. Hongki’s tone is so addictive, and you can’t go wrong when it’s given ample spotlight.

With that said, Unthinkable feels overly short. This is a common theme in today’s streaming age, and isn’t always a bad thing. I definitely subscribe to the idea of “all killer, no filler.” However, ballads like this need time to build. Unthinkable feels like it’s missing a crescendo. Hongki ensures that each chorus feels like its own mini climax, and there’s a well-placed power note during Unthinkable‘s final third. But as I listen to the song, I keep waiting for it to expand and really soar for the rafters. Instead, we’re left with a perfectly pleasant ballad. The melodies are nice – if familiar – and the band drives them forward with plenty of heft despite a stripped-down arrangement. You can’t go wrong with an FTIsland song of this nature. But, you could go just a little more right.