The dentist is poisoned and must find the antidote. Williams plants false clues in his house. This leads the police to believe Nolasco was the killer from the start. Sofía trusts him, and unexpected feelings arise between them.

Nolasco is presumed dead in prison. Sofía decides to break into the Englishman's house to find the necessary evidence to arrest him. Williams manages to take the life of someone very close to the dentist.