These young people are adrift. They've been victims of school bullying, sexual assault or their own delusions of persecution. They isolated themselves, taking refuge in their bedrooms and logging on to the internet. They made "friends" online, their only friends, on forums devoted to school shootings, Nazi ideology or jihadist propaganda. They shared videos of beheadings, photos of mass killings that resonated with their fascination with death and violence. They want to "cut off heads," to "slaughter people." They call themselves racists or jihadists. They share an inextinguishable hatred of humanity, an anger that nothing quenches, against their harassers, their aggressors, Muslims, Jews, Blacks, women, the others.

They discussed their attack plans with each other. They fantasized about killing "miscreants" or "Blacks." They made explosives and shot videos in the hope that their rage would explode in the eyes of the world, that they would be talked about, that their "work" would be remembered after their death. They were between 16 and 19 years old at the time, only children: unhappy, dangerous children.

This anti-terrorist investigation began like so many others, with a tip-off that an attack was imminent. But when they broke into the bedroom of Louna (all names have been changed), who had just turned 18, the police quickly realized that conventional counter-terrorism analysis would not enable them to understand all the nuances of this case. For while Louna is fascinated by the Islamic State (IS) organization, she also has a keen interest in Nazism. On the internet, she had discussed her attack plans with three boys who didn't all share the same convictions: one, a brilliant 17-year-old French-Japanese student, dreamt of going to Syria; the other two, aged 16 and 19, were fascinated by Adolf Hitler and planning a massacre in a high school or a mosque.

This case, a meeting point for ideologies that have nothing to do with each other, has perplexed the anti-terrorist justice system for some time. How is it possible to characterize the motives of suspects who work together on their projects, but who seem to have opposing ideas? By revealing the private feelings behind the politics and the impulses behind the grandiose speeches, this investigation is an opportunity to consider how the psychic disorders of young people in distress lead to them being drawn into radical ideologies. After two and a half years of investigation, the National Anti-Terrorist Prosecutor's Office, in a final indictment dated October 2 and seen by Le Monde, has requested that the four teenagers be tried for "association in a terrorist conspiracy."

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