Un giorno perfetto internationally released as A Perfect Day is a 2008 Italian drama film directed by Ferzan zpetek. It is based on a novel with the same name by Melania Mazzucco.
Antonio and Emma have been separated for years, but he does not accept when Emma dates other men. Indeed Antonio proves obsessive, aggressive and intrusive, and again threatens Emma to hurt the children little Kevin, shy and introverted, and the adolescent Valentina. Emma tolerates the harassment of Antonio, and the situation seems to recover. However one evening Antonio asks his exwife to entrust him with their children for an evening at a pizzeria. Antonio has a diabolical plan, and when he returns home with Kevin and Valentina, he pulls out a gun and shoots both of his children, and finally commits suicide. Emma rushes desperately to them, and discovers that her daughter is still alive...
Source: Wikipedia