With a flute, a modern pied piper leads a group of children underground.

Esther Lewanski left the police force to become a judge. However, she is worried about the disappearance of a young mother she knew: Julia Royer is suspected of having abandoned her own baby, Zoé. Convinced that Julia would never have done that, Esther decides to get involved in the investigation. But Julia remains nowhere to be found, and the case is complicated by the discovery of a young drowned woman, Charlie, whose apparent suicide finally turns out to be a homicide... Julia is said to have threatened Charlie just before disappearing. What secret could bind these two girls so apparently so dissimilar?

Married, two children, a small house: Tony ticks all the boxes of postcard happiness. But this perfection comes at a price and his end of the month would be untenable without the small deals he indulges in in secret from his family. Tony puts up with these blows to his values until Laura, one of his clients, dies of an overdose. Could the kidnapping of prosecutor Dassault be linked to this news item? This is what Maya Rosetti, pregnant, will try to discover by exploring the intimacy of a woman she knew nothing about.

We could start the story like this: Léonore Etchegarray is an investigating judge. Or so. Léonore Etchegarray, ten years in the police, two kids and a golden guy, decided to go to the other side by becoming a magistrate. In reality, it is impossible to choose one or the other. Because it takes these two facets of Léonore, these two parts of her professional life in turmoil, to, on her first day in court, cause her trouble in the face of the disappearance of Lisa Ferrer. A young executive in a high-tech company, Lisa Ferrer has not given any sign of life after a hectic work meeting. Valérie, the HR director, and Dario, the general manager, agree, but they deny any responsibility for what looks like a small runaway. For Léonore, accompanied by Commissioner Amar, there is an urgent need to clarify the exact circumstances of her disappearance...

This morning, Gabrielle Perez, a police commander, had decided to take her day off to take care of her weakened father. But this was without counting on the kidnapping of ten-year-old Elouan, who was being treated in hospital for severe eating disorders. Why precisely this child? Could this worrying disappearance be linked to the militant actions of his parents for the right to housing? The day goes by and Gabrielle will have to move forward in the twists and turns of a situation much more complex than it seems. We have to act quickly, Elouan is in danger.

On the campus of the University of Lyon, there is a buzz. Clémentine Roussin, 21, a third-year student, has disappeared... The investigation is entrusted to Commissioner Julie Sanchez, who has just been transferred to Lyon where she has decided to follow her daughter, Oriana, 18, who is in her first year of university. For Oriana, being in a roommate with her mother is a nightmare. For Julie, the involvement in her investigation is twofold. It is her job as a mother to make sure that her daughter, like all young girls, can go to university safely, it is her role as a cop to find the missing woman even if it is in the company of Patrice, a cop without ambition and not inclined to understand youth and the functioning of a university.