Carlotta's Rivalry and the 'Co-ack'
The Phantom of the OperaThe subplot of Carlotta's enmity toward Christine Daae and her public humiliation by the ghost.
increasing
Bearing strength in each event
decreasing
Carlotta's Jealousy

Carlotta's Jealousy
The Rival Emerges
Carlotta, the established prima donna, is furious when Christine Daae receives a triumph at the gala. She had been ill that night, and Christine's success threatens her position. She begins to spread rumors and use her influence to keep Christine from getting important roles.
The Anonymous Threats
Carlotta receives anonymous letters written in red ink, warning her not to sing. She believes they are from Christine's supporters. She ignores them and rallies her own friends to her side, planning to intimidate Christine during the performance.
The Night of Faust
Carlotta is determined to sing Margarita despite the threats. She is confident in her voice and her supporters. However, the ghost's intervention is not aimed at her supporters but at her voice itself.
The Toad in the Throat

The Toad in the Throat
The Fatal Note
During the Jewel Song, as Carlotta sings the line 'I feel without alarm,' her voice suddenly croaks like a toad: 'Co-ack!' The audience is stunned. She tries again, but the croak returns. The house erupts in confusion and horror.
The Humiliation
Carlotta is devastated. She cannot continue, and the performance is ruined. The ghost's voice is heard in Box Five, saying, 'She is singing to-night to bring the chandelier down!' The chandelier falls, adding to the chaos.
The Aftermath
Carlotta never recovers from this public humiliation. She cancels her contract and leaves the Opera. Her career in Paris is over. The ghost's manipulation has eliminated his rival for Christine's place on the stage.
after Christine's triumph at the gala
during the performance of Faust, the second act