In Barcelona in the early 20th century, children mysteriously disappear, but the police ignore the matter to avoid public panic, especially since the abductions quickly cease. Suddenly, the disappearances begin, with more and more children vanishing, spreading fear throughout the community. Rumors circulate that the kidnapper is actually a vampire. To counter these rumors and, more importantly, to uncover the truth behind these events, Inspector Moisés Corvo and his partner, Juan Malsano, launch an investigation, asking questions some consider extremely dangerous. However, as the two detectives delve into the investigation and uncover dangerous secrets, they find themselves compelled to pursue the truth to the end: is this vampire real, or are they being manipulated and deceived?