Prologue: Monza, 1936. Francesca, a 13-year-old girl, is lying on the muddy, wet stones on the banks of the Lambro river with the body of a dead man on her. He was trying to rape her, when he suddenly passed away. Her friend Maddalena crawls out of the water and helps Francesca push the man away. They hide the corpse in the bushes.

One year earlier, Francesca and Maddalena were not friends and nothing was meant to grow between the two girls. Francesca Strada is the only child of a quiet bourgeois couple. Her mother comes from Naples. Once a beauty who dreamt of becoming an actress, she is now a conformist woman obsessed with good manners, religion and people’s opinions. His father  owns a hat factory and seems to be a calm, passive man. While going to Sunday’s mass in her best dress, Francesca often notices a girl of her age, dark haired and wild. With her bare legs in the water of the Lambro, she is playing and catching fish with two older boys. Her name is Maddalena but she is known as la Malnata, the Wicked-One. People think she is not only a pest, but she also brings bad luck. She is believed to have caused the death of her little brother, who jumped off the window while playing birds with her, and of her father, who died in an accident at work after having argued with her.

Francesca, however, is attracted to Maddalena’s freedom and spirit. One day she manages to escape her mother’s surveillance and join her on the river. Maddalena immediately accepts her in the gang, to the great dismay of the two boys, Matteo and Filippo, who remain nonetheless under her spell. Filippo Colombo is the son of a prominent fascist family of the city. Matteo’s father is a communist. It is Maddalena’s charisma that keeps them together. They recognize her as their boss and also they fear her capacity to bring bad luck. Maddalena is a very nonconformist little girl. She often says that she is not scared by anything and crying is pointless.

Francesca begins to lie to her mother and regularly sneak out of the house, with the silent support of their maid, Franca. She even begins to spend time at Maddalena’s place – where the little girl lives with her widowed mother, her older brother Onorio, and her older sister Donatella. To Francesca’s surprise the house, despite being poor, is warm and welcoming. The first scene she witnesses when she enters the flat – Onorio patiently serving as a model to allow his girlfriend Luigia and his sister Donatella to work on Luigia’s wedding dress – is very funny and typical of the family. Onorio is a lovely guy. He works at the local factory, believes in God and fiercely dislikes Mussolini. Donatella, however, is dating Tiziano Colombo, Filippo’s brother and the older son of the most important fascist official in town. The mother is broken by the death of her husband and little boy a few years earlier. She ignores Maddalena and resents her, which must be very painful for the girl, although she tries to hide it.

Soon Francesca and Maddalena become inseparable. Francesca learns to play at the river, defy animals, get scratched by cats, don’t fear blood, and feel her body as something present and alive, not just something to dress and undress, handle and tame, as if it was that of a doll or, on the opposite, of a dangerous beast. There is only one rule: they can never play “as if” and never use imagination, as the death of her brother is still a huge trauma for Maddalena, who fears she can bring bad luck again on someone. When Francesca has her first menstruation, it is Francesca who reassures her and explains that it is nothing to be ashamed of. Together, the two girls steal fruit from the local vendor, Tresoldi, a scary and brutal man. They also get to know Tresoldi’ son Noè, who has a soft spot for Francesca and protects the girls at the cost of taking up the blame for the theft and getting beaten by his father. Later, when Maddalena needs the tongue of a dead goose for one of her rituals, Mr Tresoldi too learns to respect Maddalena’s courage and they arrange a sort of truce.

The dark shadow of the war started by Fascist Italy to conquer Ethiopia looms over the whole town. Tiziano – who is enthusiastic about Mussolini’s colonial adventure – cannot join the army because of a heart condition, but this might be a lie and he might be just protected by his powerful father. Onorio, who is against this madness, is enlisted and must leave before marrying Luigia. Maddalena, who had been expelled from school for disciplinary reasons, promises Onorio to go back and study hard. At school everyone hates and targets her, but she endures the bullying to keep the promise she made to Onorio. Soon, with Francesca’s help, her grades become excellent. However, when a mean girl called Giulia goes too far and tells her that she caused the death of several people, Maddalena curses her. Shortly afterwards, Giulia falls off the stairs and is badly injured. Everyone is persuaded that Maddalena, the Malnata, pushed her. Francesca too is briefly hesitant, which estranges her from Maddalena for weeks. Maddalena is hurt by the betrayal of her best friend and rejects her even after Francesca discovers that it was another girl, heavily bullied by Giulia, who pushed her. It will take all Francesca’s insistence to find a way to go back to Maddalena.

The winter is long and filled with tension. Foreign nations placed an embargo over Italy to punish the aggression of Ethiopia, and people complained about the economic consequences. Too many young men have gone to war. Maddalena’s family receives the most feared letter: Onorio was wounded in battle. He dies at the hospital after having married Luigia via telegram. Maddalena is heartbroken and retires from school. Tragedy strikes again when Donatella tries to commit suicide by drowning in the river. She is rescued and lays in bed with high fever. She is pregnant by Tiziano, who promised to marry her but then abandoned her and is saying around town that Donatella is a “rondinella”, that is a loose woman.

Shamelessly, Tiziano even sexually harasses young Francesca during the mass, since she is blossoming into a gorgeous teenage girl. When Noè learns about it, he confronts Tiziano but is heavily beaten by the young man’s friends. In parallel, Francesca discovers that her mother is having an affair with Mr Colombo, Tiziano’s father. And that her own father probably did nothing because Colombo helped him obtain a contract for providing hats to the Italian troops engaged in Ethiopia.

Accompanied by Francesca, Maddalena decides to face Tiziano once and for all. The young man mocks them in front of other people and goes on telling them that he is not the father of the baby, and Donatella is basically a slut. Maddalena knows the truth – Tiziano convinced Donatella to have sex threatening not to marry her if she didn’t – but also knows that people will believe Tiziano, who is a Colombo, the member of a powerful fascist family, a handsome young man coming from a higher class. She curses him, promising he will have a terrible death soon.

More determined and furious than ever, she sends him a letter which she signs as Donatella, his former girlfriend, and summons him for a meeting on the river banks. She goes to the meeting with Francesca. She has brought a pair of scissors with her. She attacks him with scissors when he tries to hurt her, but he is much stronger. He almost drowns Maddalena and then attempts to rape Francesca. Suddenly, though, Tiziano has a heart attack and dies. The girls are overwhelmed and wonder about Maddalena’s supposed power. They hide the body and go home.

The police found the corpse a few days later. At first they think it was a political murder at the hands of an anti-fascist, maybe a communist. But then they discover the letter incriminating Donatella. To save her sister from prison, Maddalena confesses the murder, accusing Tiziano of having deceived her sister and tried to rape other girls. Francesca’s name begins circulating. To escape the scandal her mother (whose affair with Mr Colombo has also become known) decides to leave town and go to Naples to visit her family for a while.

They are about to get on the train when Noè arrives and tells Francesca that Maddalena has been arrested. He convinces her to go back and tell the truth. The novel ends with Francesca telling the police what happened at the river. She might be believed, since she comes from a good family. Above all, for the first time she feels she has become strong and she has grown up. But what she really cares about is Maddalena’s friendship, the gaze in her eyes and her hand tied to her hand while they face the grown-ups.