If caterpillars could become butterflies and continue morphing into something else entirely unknown afterwards, that’s the story of Debut, Post, and Björk’s third ’90s opus, Homogenic: constant evolution causes expansion. At the peak of one of the strongest streaks in pop music here, Björk experiments with electronica, trip-hop and classical string arrangements to craft a classic of its time. Her poetry atop the magisterial production on tracks like “Unravel” and “All Is Full of Love” will place a lump in your throat.