"O Filho Único do Pai" tells the story of Lucas, a frustrated logistics analyst who tries to pull himself together after being betrayed by his fiancee. And when everything looked bad enough, Antônio, his father, an eccentric retired actor, reappears after a long time and forces his son to make decisions that will change the direction of his life.

A year after the disappearance of his son, Thomas Mathews, an investigative journalist, still has no information and begins his own obsessive search. However, the obsession has him losing his house and job so his boss sends him on special assignment in Brazil. In Brazil, Mathews investigates close encounter sightings that have taken place in the small cities of Quixada and Quixeramobim-also known as Area Q. While there, he realizes he will face the biggest discovery of his life.