Gérald Caillat helms Maria Callas: Passion Callas , a feature-length documentary exploration of the woman who became the most accomplished and gifted operatic diva of the 20th century. Caillat creates a biographical portrait by interweaving archival film footage of legendary Maria Callas performances with interview footage of Callas, her mentor Elvira de Hidalgo; her stage producer Luchino Visconti, and her recording producer Michel Glotz. The film functions as a companion piece, not only to innumerable audio recordings and filmed performances of Callas, but to Franco Zeffirellis 2004 feature Callas Forever and to the preexistent 1978 documentary Callas: A Documentary directed by John Ardoin. ~ Nathan Southern, All Movie Guide