Just as a young woman is about to marry her sweetheart, she is discovered—by the entire village, to say nothing of her fiancé—asleep in the bedroom of a stranger. It takes the young man two acts to figure out that sleepwalking is to blame, and everything ends happily. Natalie Dessay as Amina and Juan Diego Flórez as Elvino deliver bel canto magic and vocal fireworks in Mary Zimmerman’s 2009 production. The Tony award-winning director transfers Bellini’s bucolic tale to a rehearsal room in contem...