In August 2016, the discovery of the lifeless bodies of Marcos Campos, Janaina Santos and their children, María Carolina and David, aged three and one, confronts investigators with an unprecedented case: the first crime shared on WhatsApp. Very soon, the investigations of the Police point to Patrick, a 19-year-old boy, nephew and cousin of the victims. A law student, from a wealthy family, who had come to Spain to fulfill his dream of being a footballer. By the time the investigators gather all the evidence that incriminates him, the young man has fled to Brazil. Bringing him back to Spain will be a challenge. But this family drama takes an unexpected turn. Some WhatsApp conversations are made public. Patrick, the main suspect, had a seven-hour conversation through this social network with his best friend, Marvin, who lives 6,000 kilometers away, in the Brazilian city of Joao Pessoa.