While the police are in the house with Gigi and Renato, the grandmother returns and gets scared. Although Renato declares himself innocent, he tries to escape but Gaetano manages to stop him. At Camilla's house, Livietta has a proposal for her father.

The news of the American tourist's murder is broadcast on television when Camilla returns home and finds Renzo very nervous about his project, which, according to him, is missing something.

Gaetano finds himself evaluating his future in-laws' proposal and must also give his professor friend's contact to his fiancée. Renzo is updating everyone on the project and the lighting-related modifications.

There's a bit of chaos in class between Aiello and some classmates, Camilla is forced to calm things down. The victim had purchased some diamonds that have disappeared.

Gaetano meets Camilla at school before Gaetano arrives to ask her for a favor. Both seem to want to hide something from their respective partners. Gaetano and Torre talk to the jeweler again.

Livietta tells Camilla that her grandmother promised to give her a tropical fish. Renzo still doesn't know anything about it, and when Camilla proposes it to him, he is adamant. Meanwhile, during the search at Aiello's, something is found.

Renato is questioned after one of the diamonds was found in his room. Camilla wants to believe he is innocent until proven otherwise while the principal already thinks he is guilty. Meanwhile, Roberta will meet Camilla for dinner.

Livietta is still trying to figure out how to convince her father to get a fish. Camilla, before going to dinner with Roberta, stops by to say hello to Renzo who is busy with his important project.

Camilla is finishing dinner with Roberta and Renzo is about to leave to pick her up when he is stopped by Andreina who wants to try to convince him to reward Livietta. At Hotel Bisanzio, Camilla and Roberta encounter a somewhat embarrassing situation.

After dinner, the two couples meet a colleague of Renzo who is also the boyfriend of the Teatro Marcello victim's sister.
The next day, Gaetano and Torre speak again with the suspect, but Camilla is also listening.

During Nando's interrogation, a detail finally emerges that Gaetano can then investigate. After speaking with the suspect, Gaetano goes to visit Meg, the victim's sister.

When Gaetano meets Meg, he tells her that his sister Holly had a relationship with Marinetti. Right after, Torre informs Berardi that Marinetti is dead and some details emerge.

Gaetano rushes to the hotel to talk to Meg right at the moment when she was leaving. By now it's clear how things went between the two sisters and Meg tells the real reason for the argument.

After Meg's confession, Gaetano and Camilla go to dinner to discuss the conclusion of the case. While talking, Gaetano asks Camilla something but at that moment she receives an emergency phone call from home and rushes away without answering.