The soprano was determined to finish the performance, but, according to the Tribune, she was in a lot of pain. She mimed her role without singing up to the great crypt scene, which closes the opera, when her co-star Stacey Rishoi, who was playing the role of Amneris, unexpectedly began to sing Lister's lines for her from backstage.

The audience, according to the paper, was pleased. Conductor Anton Coppola said, "It was a heartwarming moment, an exciting moment. And the best thing is the audience didn't feel cheated."

What happened to Lister is still unknown. Coppola said, "I noticed a decline in her vocal powers from when the opera began."

Judith Lisi, president of the performing arts center, said, "She said it felt like a hairball. She couldn't sing, and had to walk off. She was trying to gargle it up, but couldn't move it."

Robert Swedberg, general director of Orlando Opera, which co-produced Aida with Opera Tampa, said, "I don't think it was vocal strain. It was something she inhaled and as she tried to sing over it, she knew it wasn't going to work."

One theory is that Lister inhaled a piece of the decorative confetti that floats onto the stage as part of the production.