Passenger's "Let Her Go," released in 2012, opens with a deceptively simple chord progression — C, G, Bm, D — that immediately sets its bittersweet, reflective tone. The movement from the settled warmth of C major through the openness of G and into the minor pull of Bm gives the sequence a gentle ache before D resolves it forward with quiet momentum. That slip into Bm is the emotional hinge: it introduces a wistfulness that feels both inevitable and tender. Strummed fingerstyle on an acoustic guitar, the progression has a natural, unhurried quality that sits perfectly in the indie folk-pop sensibility of the early 2010s. It rewards players immediately, feeling both approachable and emotionally resonant from the very first bar.