Kristine Opolais stars in the role that helped launch her international career, the mythical Rusalka, who sings the haunting “Song to the Moon.” Mary Zimmerman brings her wondrous theatrical imagination to Dvořák’s fairytale of love and longing, rejection and redemption. Brandon Jovanovich, Jamie Barton, Katarina Dalayman, and Eric Owens complete the all-star cast, and Mark Elder conducts.