The actual story is very complex, took place over more than 30 years, had lots of fits and starts, with many characters, like the judges, doing only one thing at some point and then moving on with their careers, so the series is only inspired by the actual case. As a result, the story has been massively streamlined, by only focusing on six steps: the first attacks, the judge trying to move the case forward, the mayor going public with the attacks, the scientist working on the attacks' data, the real police investigation and the catching of the rapist. Consequently, many "subplots" were completely removed: Dino Scala's first marriage, his first attacks on his first wive's sisters, the investigation by the archivists who first linked together dozens of sexual attacks in the area in the 90s, the many many attacks and victims who are not shown at all but simply mentioned near the end, and of course, the trial. Also, several characters are not real, but they're amalgamations of several existing people, most notably the first victim in the series. As a result, all character names were changed. For example, the real life rapist Dino Scala is renamed Enzo Salina here, mayor Annick Mattighello is called Arlette Caruso in the show, etc.

This series is based on a true story, the case of the Sambre rapist, and adapted from the book "Sambre, radioscopie d'un fait divers" (meaning "Sambre, radioscopy of a news item" in English) from journalist Alice Géraud, which came out in January 2023, the same year the series was first broadcast. This was made possible by the fact that Géraud was also the co-creator of the series.

Sambre is the name of the river alongside which all the attacks happened.

Sambre denotes the Samber River, the nearby location for the attacks near Lille in Northern France and not far from the border with Belgium and nearby Bruges.