If the last decade in pop music has taught us anything, it’s that nostalgia can be a double-edged sword. When it goes wrong, it’s about as satisfying as swallowing a mouthful of processed spray cheese. When done right, revisiting the tropes and aesthetics of decades past can go down nicely. M83’s 2011 double album, Hurry Up, We’re Dreaming, fell into the latter camp and—bolstered by its ubiquitous single “Midnight City”—transformed Anthony Gonzalez’s curious 15-year-old project into a soundtrack for Victoria’s Secret commercials and Tom Cruise sci-fi flicks. Surely this shift explains something about the new M83 album, the fascinating and somewhat flummoxing Junk.