¡Vaya par de gemelos! (1978)

Lucas and Pedro (Paco Martínez Soria) are identical twin brothers from the small Aragonese town of Tarazona. Pedro has everything in life: an understanding, sensitive wife (Margot Cottens), a good job as the head of a chocolate factory, and all kinds of luxuries and trips. Lucas, meanwhile, is the complete opposite: he lives with his wife (María Isbert), who keeps him under control at all times, and works for her in a small shop in town, which he has never left. Tired of this kind of life, and since his wife never stops comparing him with his brother, Lucas goes to talk to Pedro. He asks him to help with a small problem he has with a tax payment and to explain how he can live more like Pedro does. Seeing that his brother is having a very hard time, Pedro decides to reveal his big secret: he had made up the story that he had fathered a child before his marriage. When he told his wife about it, she agreed to give him money for the child’s education and upbringing, while he spent that money on trips to cabarets and parties in Madrid. There he met a young man named Jorge (José María Guillén), whose trust he won so he could steal the young man’s school records and photographs, then hand them over to his wife and convince her that his son existed. Seeing that this could improve his life, Lucas decides to make up a fake son of his own. But his wife is not at all understanding: she cannot forgive him for this supposed indiscretion before their marriage, or for not giving her a child after so many years of marriage. Pilar (Inma de Santis), Pedro’s real daughter, tells her parents that she is going to get married. They are delighted, and when her mother realizes that Pilar will be leaving home and they will be left alone, she asks Pedro to tell his son to come and live with them. As the situation becomes more complicated by the moment, Pedro invents another lie, saying that his fake son has just died in a car accident, and uses this as an opportunity to get more money from his wife to cover the funeral expenses. The surprise comes when Pilar’s fiancé turns out to be Jorge, who shows up unexpectedly at her parents’ house to announce their marriage. When Pedro realizes that his fake son is about to become his son-in-law, he makes up more lies in an attempt to further entangle the story.