Barcelona 1952. General Franco's fascist government is at the height of its oppressive powers, casting a black shadow across the city. When wealthy socialite Mariona Sobrerroca is found dead in her mansion in the exclusive Tibidabo district, the police scramble to seize control of the investigation. Eager young journalist Ana Martí Noguer is surprised to be assigned to this important story, where she must shadow Inspector Isidro Castro. But Ana soon realizes that a bundle of strange letters unearthed at the scene of the crime points to a sequence of events dramatically different from the official version. She enlists the help of her cousin Beatriz, a scholar, and what begins as an intriguing puzzle exposes a series of revelations that implicate the regime's most influential figures. The two women have placed themselves in mortal danger. As the conspiracy unfolds, Ana's courage and Beatriz's wits will be their only weapons against the city's corrupt and murderous elite.