Folks who saw loudQUIETloud, the 2006 Pixies reunion documentary, likely noted Kim Deal scribbling notes for new songs and quietly rejoiced. They were right to. Though Mountain Battles opens with a somnambulant, glazed-over half-song, in the end this is no sad Pixies hangover: The quiet, eternal strangeness of the Deal sisters soon emerges, an old flame you didn't know you were still nuts about. Their damaged, girlish voices and aggressively human guitars are put in service of newly low-key songs that conceal dark and throbbing hearts. Surprises (a bolero, a country song) abound.