The series tells the story of Sonia Ledesma (Michelle Calvo), a police inspector who joins Group 2 of the Disappeared of the Central Brigade, led by veteran chief inspector Santiago Abad (Juan Echanove). Affected herself by the drama of the disappearance of a close loved one, she will find in her companions Rodrigo (Maxi Iglesias), Sebas (Chani Martín) and Azhar (Amanda Rios) a new family. Together with them, and with the motto “we keep on searching”, they try to solve the most disparate cases, all of them carried out by people who one day swallowed the earth. To achieve this, they have the collaboration of Ayuda Desaparecidos, an NGO led by Carmen Fuentes (Elvira Mínguez).