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.

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.

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.

Anna and Camilla enter Quantunque's apartment to understand why he hasn't been to the restaurant anymore; the only suspicious element is a suitcase locked with a combination. Meanwhile, at home, Renzo appears more serene after talking with his mother-in-law and attempts a reconciliation by preparing dinner.

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.

A song about pain and heartbreak serves as background to the students who receive news of maestro Marioni's absence, due to a minor accident. The suspension of orchestra rehearsals generates different reactions among the young people, between relief, expectations for an upcoming concert and reflections on shared work.

A mysterious phone call casts Lojacono into shadow: a stranger from Agrigento hints at an unpaid mortgage and lets slip a veiled threat.
Meanwhile, Romano focuses all his anguish on little Giorgia. Between fear and hope, the doctors try to reassure him about the child's condition.

Gaetano notices that Camilla is more serene and she confides in him that Renzo, too, finally seems to have calmed down. However, the peace is shattered when Ventruti reaches the commissioner to get confirmation about the identity of the woman found dead. Devastated, the man lets all his pain emerge and reveals details that could prove crucial for the investigation.

The physicists describe their amazement at the grandeur of the detector, a symbol of collective scientific effort that unites different cultures to understand the universe. A work compared to a cathedral, an expression of science as part of civilization's progress.

In this moment of confrontation, Irene and Luca face the consequences of what happened, while within the group of students tension grows between some of them. Between misunderstandings, sense of responsibility and need for closeness, emotional conflicts and fragments of daily life alternate.

While Romano talks with the doctor, he meets Giorgia at the hospital, who is there to assist her hospitalized mother. Meanwhile, at the police station, new clues emerge about a suspect linked to a criminal clan, while Laura and Giuseppe share moments of complicity that lighten the tension of the investigation.

Camilla finds herself involved in the difficult situation of one of her former students, obsessed with Quantunque, who has mysteriously disappeared and whom she wants to help at any cost. Between enigmatic messages and a photograph that has resurfaced from the past, the investigations proceed amid suspicions and uncertainties, without yet a real breakthrough.

In this part Fabiola Gianotti talks about the connection between science and creativity, combining physics and music as universal forms of expression. She also explains the work of the Large Hadron Collider, where proton beams are made to collide to study the universe right after the Big Bang.

Marioni is forced to give up conducting the concert due to his injury, while Rosario receives an affectionate visit from his mother, between tenderness and a touch of embarrassment. In a record shop, unexpected confidences emerge and, once again, between music and complicity, the young people confront love and friendship.