Alagna, pictured, famously stormed off the stage at La Scala in 2006 after the notorious upper balcony booed his opening aria as Radames in “Aida.” Mezzo-soprano Ildiko Komlosi, who was playing the princess, Amneris, was left on her own until understudy Antonello Palombi popped up in street clothes. Alagna returned as Radames -- replacing an ailing Marco Berti -- at the Metropolitan Opera in New York in 2007. This time, the audience cheered. (AFP / Getty Images)
