La Luna, also known as Luna, is a 1979 Italian film directed by Bernardo Bertolucci and starring Jill Clayburgh. The film concerns the troubled life of a teenage boy and his relationship with his parents, including an incestuous relationship with his mother.
Caterina is heartbroken and hopes to lure her son back to a safer and more healthful lifestyle. She tries in many instances to get closer emotionally to her son hoping that increased contact will prevail over the pull of the drugs. She even contacts his drug dealer to ask for sympathy for her situation. At one point, when Joe is desperate for a fix, his mother masturbates him just to get his mind off drugs temporarily.Seeing no other alternative, she decides to drive to the location they originally lived, where her estranged lover lives with the hope that some sort of fatherly bond will cure her son. Along the way, tensions, some sexual, derail and prolong the trip. Eventually the son is dropped off at the exs home, but Joe, rather than telling his father that he is his son, says that he is instead a friend of his son, and that his son overdosed on heroin after lifelong turmoil over the absence of his biological father. With some sort of closure achieved for the boy, he returns to his mother who is preparing for an opera. Embracing, they reaffirm their love for each other, and together the son and his father, who has come to watch the performance, and who now knows Joes true identity as his child, hear Caterina sing at her very best. ........
Source: Wikipedia