It has been a while since Inspector Amaia Salazar confronted her mother. But despite the fact that both the Civil Guard and Judge Markina consider the case closed, Amaia feels that she is not free from danger. The sudden death of a baby girl in Elizondo is suspicious and the forensic analysis leads Amaia to investigate other deaths of similar origin that will lead the inspector to the final resolution of the events that have devastated the Baztán valley.