Matteo tells us how fundamental it is to know the entire score, not just one's own part, in order to best interpret a piece. For him, music is above all education in listening: to the composer, to other musicians, and to oneself. Playing together thus becomes an experience of growth and mutual care, even before it becomes artistic.

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.

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.

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.

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.

Sometimes the accompanist has to follow the soloist's musical intentions, but at other times, when the musician is not very experienced, the accompanist needs to guide the soloist and make the best of a potentially tricky musical situation. This depends on the musical and technical level of the soloist, as well as the experience and maturity of the accompanist.

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.

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.

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.

Pianist Matteo Bogazzi explains what his job — pianista collaboratore (collaborating pianist) is all about, and how he got there. The interview took place during a chamber music festival and summer course in Lucca, where he was working.

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.

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.

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.

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.