 In Seville, the newcomer detective Maria Delgado arrives during the Holy Week and is assigned to work with detectives Quemada and Torillo in the bizarre murder of twins, killed with several bullfighter knives. Maria interviews the old lady Ms. Catalina, who found the bodies, while a tourist is attacked on the streets by a masked guy with a bullfighter knife. The trio connects the cases and follows the lead to a brotherhood. The director of the brotherhood is also killed by a knife, and Maria follows her instinct and visits Ms. Catalina again in a convent. Ms. Catalina discloses her sad adolescence when Spain was in Civil War and Maria gets closer to the truth.