Lojacono pursues and arrests Donato Cuocolo. After attempting to flee and threatening the officers with a brick, he is stopped by Alex Di Nardo. At the police station, the investigators put him under pressure: he risks many years in prison, but he can face a lighter charge if he cooperates.

Gaetano and Roberta argue heatedly about the wedding preparations and family responsibilities; the argument angers Roberta, who decides to leave. Meanwhile, Camilla asks Gaetano for help and, thanks to a photograph, a young man is connected to the woman found murdered. For this reason, Gaetano wants to speak with Anna to get more information and deepen the investigation.

Here is the account of the startup of the Large Hadron Collider at CERN on September 10, 2008, when for the first time proton beams began to circulate in the accelerator ring. The event, followed live by the media, is presented as a historic moment for science, despite the fears and catastrophic news spread in those days.

Rosario finally meets his mother during a visit. The two speak with affection, but also with a certain embarrassment about Antonia's difficult past, who however tells him she is feeling better and has reduced her medication. The woman then tries to learn more about her son's life, asking him about school and his friends. Meanwhile, Barbara is scolded by her mother because she is always glued to her phone.

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.

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.

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.

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.

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.

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 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.

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.

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.

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.

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.