LONDON, ENGLAND - SEPTEMBER 09:  Brindley Sherratt as Oroveso, Sonya Yoncheva as Norma and Joseph Calleja as Pollione with artists of the company in the Royal Opera's production of Vincenzo Bellini's Norma directed by Alex Olle and conducted by Antonio Pappano at The Royal Opera House on September 9, 2016 in London, England. (Photo by Robbie Jack - Corbis/Corbis via Getty Images)Sonya Yoncheva as Norma, Joseph Calleja as Pollione,