Reported by BBC World
Watch: "It destroys people, but we all make our own choices" - Marseille drug-gang members talk to BBC
Although she had just bought hashish from a drug dealer, the woman decided to call the police.
It was because, along with the illegal drugs, she had been handed a note by the young seller during their brief meeting on a Marseille housing estate in 2022.
More from the original report
"We're being held captive and need help. We are 15-years-old," it read.
The teenage dealer, a French court heard earlier this year, was one of two boys being held by a gang which they had both initially approached looking for paid work - albeit illegal.
One boy had been tasked with handling money, the other worked streets around the Frais-Vallon estate. Soon though, bosses had accused them of being responsible for "shortfalls" in takings.
What followed were regular beatings, the court was told, and being forced to dance naked in front of a camera as a form of blackmail. One of the boys was also raped.
Hours after the woman was passed the note, the two teenagers had tried to escape from a second-storey window, injuring themselves in the process. One managed to get away, while the other was caught, beaten and stabbed, but survived.
Arrests were made. Photos on the phone of one of the boys' alleged torturers showed several other young men in a similarly distressed condition. Six men have since been handed hefty sentences for what happened to the two teenagers.
The boys' story highlights the grip that drug gangs hold over parts of France's second city.
While the blend of Mediterranean culture, street art and hip-hop scene has made Marseille a popular tourist destination - beyond the city centre, it is another story.
After months of trying, a BBC team managed to enter this dangerous world - centred on deprived streets and high-rise housing estates in the port city, which police do not enter lightly.
We found an environment where ruthless gangs lure vulnerable young people with promises of easy money, but end up trapping them in a world of drug dealing,…