In the U. S., the film was screened in several cities in two three-hour parts. The two-disc DVD of the film is similarly divided.
Giordana, who directed a film about the suspicious circumstances surrounding the death of poet and director Pier Paolo Pasolini, again paid tribute to the director in this film, as its title comes from a Pasolini poem. The film falls within the tradition of several Italian films that cover expansive times of Italian history through the story of one family, such as Rocco and His Brothers and The Leopard.
The Best of Youth is a family saga set in Italy from 1966 through 2003. It chronicles the life of an Italian family, the Caratis, but focuses primarily on two brothers, Matteo (Alessio Boni) and Nicola (Luigi Lo Cascio), documenting their journey from the prime of their wild youth in the mid-1960s counterculture, to parenthood and retirement in the early 2000s. The film aims to show the interaction of the personal and the political, the ways in which small events may become turning points in the important choices made by individuals.
Two brothers go their separate ways after attempting to rescue a young girl, Giorgia (Jasmine Trinca), from an abusive sanitarium. The brothers are Matteo and Nicola Carati (Alessio Boni and Luigi Lo Cascio). Their parents are Angelo (Andrea Tidona) and Adriana (Adriana Asti), their older sister is Giovanna (Lidia Vitale), and their younger sister is Francesca (Valentina Carnelutti). Their friends, their lovers and others drift through, including Giorgia who struggles with mental issues, but whose life seems to follow in parallel.
Matteo walks out of his first exam, while Nicola qualifies as a doctor (and will pursue a career in psychiatry). Matteo takes mental patients for walks to help them begin to feel normal and takes a particular interest in his patient Giorgia. Noticing that Giorgia has been wounded by electroshock therapy, he decides to remove her from the institution and take her along with him and Nicola—who are about to go on a trip to Norway.
Eventually, Giorgia is captured by the police and taken back to the asylum. Matteo, filled with sadness and depression, returns to Rome and joins the army. Nicola continues to Norway and gets a job as a lumberjack. The brothers meet again in Florence just after the 1966 Arno River flood. Here, Nicola meets a university student, Giulia (Sonia Bergamasco).
Nicola and Giulia are living together in Turin, but the two do not marry.
Matteo leaves the army and joins the police force. During this time, Matteo shows signs of continuing depression and anger. He accepts an assignment in Sicily, a place corrupted by the Mafia. Meanwhile, Nicola and Giulia conceive and care for Sara, their daughter.
In Sicily, Matteo meets a photographer in a caffè named Mirella (Maya Sansa). She wants to be a librarian, and he advises her to work at a beautiful library in Rome.
Because of his temper, Matteo is forced to leave Sicily. He decides to reside in Rome but refuses to visit his mother.
Meanwhile, Nicola becomes a psychiatrist, and works to eliminate the abuse and maltreatment of patients in mental hospitals. He finds Giorgia in one of these hospitals. She is tied to a bed in inhumane conditions, does not talk, and shows fear of being touched by others. After some time, Giulia gets drawn into a secret Red Brigades cell. One night, she leaves Nicola and Sara and disappears into the terrorist underground.
Years later Matteo walks into that same library and sees Mirella for the second time. They fall in love, and one evening, make love in a car. Eventually he pushes her away.
Mirella meets with Matteo with news for him, but he behaves harshly and forces her to leave. On New Year's Eve, Matteo decides to finally visit his mother. Everyone is there to celebrate. Instead of waiting for the traditional toasts, however, Matteo decides to leave early and, at midnight, jumps off the balcony of his apartment and kills himself.
The family is devastated by the tragedy. No longer motivated, Nicola's mother quits her teaching job and lives a life in solitude in Rome. Nicola, feeling that he could have saved Matteo and not wanting to make the same mistake again, arranges for the capture of Giulia to prevent her from killing someone else or from getting killed. She is sentenced to 17 years in jail. During her jail term, Nicola visits Giulia and proposes to her but is rejected.
Nicola finds a photograph of Matteo taken by Mirella. He is encouraged by Giorgia to meet with Mirella which, after some hesitation, he agrees to do. When he meets Mirella, Nicola learns about her son (Andrea) and that Matteo was the father. Nicola breaks this exciting news to his mother and they visit Mirella and the boy on the small island of Stromboli. Inspired by new meaning in her life, Nicola's mother decides to stay with Mirella and her grandson.
Meanwhile, Sara, now in her early twenties, is still struggling with the poor choices her mother has made. She decides to move to Rome to study art conservation and becomes engaged to Mimmo. During this time, Nicola finds out his mother has died and, as a result, travels to Stromboli to visit Mirella and pay his respects.
Having finally moved past the death of Matteo, Nicola and Mirella fall in love. Sara, now happy and strong, is encouraged by Nicola to confront her mother and try to patch things up. Giulia, now out of jail and in desperate need of love, embraces Sara, but is not ready to open up completely.
The film ends with Matteo's son, Andrea, visiting Norway, specifically North Cape, which is where his father and Nicola ventured to go at the beginning of the movie, but never completed their journey.