After the mysterious murder of the Spanish ambassador in Lisbon, Teresa follows a lead to a young girls’ academy in Seville. Teresa decides to pose as a teacher and applies for a place at the academy.

Due to a trip to Madrid, Manuela leaves the academy in Luisa's hands, who asks Doña Manuela to help her and revive an old tradition: the Capsule. Roberta tries to contact her parents while Flavia tries to hide her feelings for Tomás.

Teresa continues to unravel the investigation when a mysterious note makes her flee. As the end of the semester approaches, the academy faces a serious economic crisis.