However much Callas had grown fond of Onassis, she did not allow other people to interfere in her professional affairs. Until mid-1965, Maria Callas continued to give opera performances, albeit much less in number – despite Onassis’ advice to make films. In late 1960, she even returned to La Scala in Milan in the opera Poliuto (Gaetano Donizetti), though she did not sing the lead role.

On October 29, 1956, Maria Callas made her debut at the Metropolitan Opera in New York in the role of Norma from Vincenzo Bellini’s opera of the same name. It was not foreseen that the aria “Casta Diva” from Norma would find in Maria Callas one of its most famous interpreters: “Norma” was still quite unknown to the audience of the Met and many spectators were only coming to see Callas live for the first time.

Arriving in New York and staying with her father, who lived there, little promising happened at first: more than once she recited for other opera singers and directors, who always told her that she still needed to work on her voice.
Maria soon suspected that she would have little chance of launching a career in New York.

By the end of 1956, Greek-American opera soprano Maria Meneghini Callas had several offers on her desk from well-known publishing houses, all competing to publish her memoirs. She turned down all the offers.
Now she was faced with the problem that many inaccuracies or, much worse, untruths about her person and her career were spreading.