Sandra was born in the province of Pisa and tells the story of her personal transformation. She begins at the beginning, when she was a young girl growing up in Cascina, a town near Pisa. But she wasn't happy and felt like a fish out of water.

During the meeting with his mother, Rosario discovers that she wants to move to Florence and come back to live with him. The news upsets him, because he has been living with his foster family for a long time and fears that this sudden change could turn his life upside down.

On March 30th, 2010, the first proton collisions took place in the Large Hadron Collider, a historic moment for physics. After 20 years of work, the scientists celebrated the success of the event, marking the beginning of a new era in scientific discoveries.

When Gaetano realizes that the briefcase found by Anna and Camilla has mysteriously disappeared, the commissioner becomes furiously angry. During the investigation, it emerges from Mr. Ventruti that Quantunque knew Flora and was protecting her.

At the police station, lawyer Nubila shows up to offer his financial support for Lara's daughter's medical care, declaring that he has no financial difficulties. During the meeting, he receives a phone call from his wife, who asks for updates on Lara's husband, currently among the main suspects.

Marika explains the school evaluation system in Italy, illustrating grades, exams, report cards and electronic registers. The lesson also includes the meaning of useful terms and expressions related to school life, helping to better understand how the Italian school system works.

An everyday conversation brings to light small obsessions, embarrassments and emotional difficulties. Between jokes about recycling and seemingly insignificant gestures, deeper tensions emerge: the struggle to ask for help, the need for connection and a subtle loneliness.

The world of research can also be told with lightness and self-irony: through traditions like an annual play, scientists transform discoveries and great protagonists into opportunities for joking and sharing, revealing the more human and fun side of theoretical physics.

Gaetano and Roberta go through a story made of everyday life and tension, in which arguments and reconciliations follow one another. Meanwhile Camilla discusses with Anna the suspicion that Quantunque might be involved in shady business.

The investigation into Lara's death continues, while the police conclude the interrogation of the suspect. Meanwhile Aragona, in order to go out with Irina, promises her that he will find the culprit.

This vocabulary lesson is dedicated to school: Marika illustrates the main school activities, such as studying, reviewing and taking tests, along with the most common subjects, explaining their meaning with simple and clear examples.

Rosario and his mother share a secret and touching moment in the school that the boy attends, between music and complicity. At Matteo's house, instead, tensions emerge between uncle and nephew, fueled by emotional conflicts and misunderstandings.

Fabiola Gianotti's account retraces a serious technical incident that affects a major scientific experiment, the initial shock and the subsequent recovery. In parallel, her personal reflections and the strong emotions linked to the responsibility of leading the project emerge.

Camilla needs to speak to Anna and phones her, only to find out that Anna had just forced the briefcase open at Quantuque's place. Meanwhile, the investigators interrogate a witness who points to a possible suspect.

The police interrogate Cuocolo after the arrest and he tells of having met Lara on the Mergellina waterfront and of having had a casual relationship with her. However, he denies being the father of the child and claims to have an alibi for the night of the murder, suggesting that the culprit could be someone in love with her who was not reciprocated.