Fabiola and her colleagues retrace the long journey toward the discovery of the Higgs boson: from Peter Higgs' theoretical intuition to the difficult meetings at CERN, up to the realization of the Large Hadron Collider, initially considered almost impossible.

Rosaria appears very impressed by Alex's new house and, between one compliment and another, updates her partner on the latest developments in the investigation. Meanwhile Lojacono goes to the restaurant to see Letizia, who welcomes him by offering a rich and inviting selection of typical Neapolitan dishes.

Rosario is troubled and, returning home, confides to his foster parents that he will meet his mother in his own way, alone. Meanwhile, Sofia and her brother exchange sharp remarks, while Marioni relives memories from the past, and a sudden bicycle accident transforms a quiet evening into a moment of great apprehension.

Anna is worried about Quantunque and asks Camilla to accompany her to his house to understand how he is, since he didn't come to the restaurant. Meanwhile, Torre and Piccolo enter Torrielli's apartment, finding it completely turned upside down: no clear clues emerge, except for elements that suggest an ambiguous professionalism.

In this part, the encounter with physicist Fabiola Gianotti at CERN is retraced, highlighting her scientific talent, humanity and prominent role in international research. Between personal memories and reflections on theoretical and experimental physics, the importance of collaboration between the two fields emerges, recalled by the example of the discovery of the Higgs boson.

Between interrogations, conflicting leads and multiplying suspicions, secrets emerge linked to the victim and their private life. Meanwhile Romano faces the weight of his own guilt and the violence he committed but is called back to a sense of responsibility by the group.

Through song, Matteo, rejected by Barbara, who chooses to remain just a friend, expresses his pain. Sofia's unconfessed feelings also emerge, as she loves Matteo in silence.

Commissioner Berardi investigates the disappearance of Mrs. Torrielli and, during an inspection, interrogates the widower Ventruti. In an informal setting, over coffee, an important detail emerges: Flora's new address.

In the video Renzo Piano and Fabiola tell about CERN as a symbol of the cultural and scientific rebirth of the post-war period. Through personal memories and everyday dialogues, CERN emerges as a place of human and international encounter, founded on curiosity, peaceful collaboration and love for knowledge.

Mrs. Nubila retraces what she knows about Lara, the young woman welcomed with almost filial affection into her family. However, the fragile balance of her life is shattered by her husband's sudden return. Di Nardo and Lojacono reveal to her an aspect of Lara's story that the woman was unaware of.

The group gets together for an evening among friends, marked however by some absences. Between relationships that are ending and unexpected revelations, the group still tries to stay united. A final toast celebrates a friendship that endures, despite everything.

Camilla introduces a reflection on couple relationships drawing inspiration from literary examples, to analyze the theme of women who are socially and economically stronger than men. Meanwhile, Torre and Berardi conduct a neighborhood investigation that leads to gossip and everyday banality, between soap operas and moral judgments.

Fabiola Gianotti describes CERN as a place of encounter, growth and international cooperation; a young and multicultural environment where science is experienced in a democratic way. The archival images celebrate the original spirit of CERN: an extraordinary adventure.

Ottavia and Romano speak with Senatore who tells about his ambiguous relationship with Lara, described as an honest, reserved woman full of grace. After rejecting his advances, Lara decides to leave suddenly and when he is told that she was pregnant, the man appears genuinely surprised.

Marioni interrupts a lesson by his colleague Guido and harshly confronts Nathan, ordering him to show up for rehearsals with the others. The tensions center around Sara, causing conflicts to explode in the group and bringing personal vulnerabilities to light.