Back in late 1963, a Belgian nun known only as Soeur Sourire, or Sister Smile, topped America's pop music charts with the relentlessly cheerful tune "Dominique," from an album that sold 1. 5 million copies. From the little that is known of the ill-fated nun's life, Roger Deutsch has made the boldly speculative yet persuasive Italian-language film "Suor Sorriso" in which the nun (Ginevra Colonna) emerges as a tormented, unstable woman who abruptly left the convent after her recording triumph before taking her final vows. Running a shelter for wayward girls, she and another ex-nun (Simona Caparrini) enter a passionate, tumultuous and destructive affair. Colonna's volcanic Deckers craves spiritual redemption as well as the other woman's love but is so beset by demons that she embarks on a flamboyant, drug-fueled downward spiral that ultimately engulfs her lover as well as herself. This film is in Italian with English subtitles.