Artists know exactly who to call when they’re itching to push their boundaries: St. Vincent, who lends a dark, sexy—if not slightly woozy—sound to anything she touches. The singer/songwriter/guitarist has slyly put her stamp on country, pop, and indie, slipping dissonant guitar into The Chicks’ “Texas Man,” sending Taylor Swift through an industrial dreamland on “Cruel Summer,” and gorgeously locking vocals with Bon Iver for “Rosyln.”