Inspector Elena Blanco has discovered that her son Lucas is alive, but belongs to the sinister Purple Network, which Vistas told her about before its dramatic denouement. Six months have passed and the inspector hides from her team that her son is among them; Only Mariajo, her faithful confidant, knows the truth. The BAC has been penalized by the outcome of the Macaya case, being transferred to another ship and the only thing they can do is pull on that thread that Vistas left them, a network that is hidden in the depths of the interns.
Sister Marina, a very unorthodox nun, is sent during the summer of 1994 to El Parral, a boarding school for boys threatened to be closed soon. Even though the kids welcome Marina with all kinds of pranks, they will, little by little, become something very close to the family they never had.