Opera photos | 2. November 2017 All photos: Erik Berg, The Norwegian National Opera and Ballet Cover art by production designer Hans Petter Harboe. Violin virtuoso and vagabond, Nagel causes unease. Nagel with Dagny. The inhabitants of the small village: “A stranger has arrived in town.” The main character, Nagel, tormented by visions. “Mysteries” is also a love story. Nagel with Dagny.