"Flume" emerges from a period of isolation and reflection, born from Justin Vernon's retreat to a remote cabin after illness and frustration. The song, like the album it belongs to, was crafted by first creating wordless melodies and then finding meaning in the subconscious sounds, a process that revealed "grudge and meaning" within the syllables. It carries themes of lost love and longing, reflecting a deep personal journey during which Vernon abandoned old songwriting methods. Playing it can feel like channeling a raw, intimate search for understanding amidst solitude.