Ugo, Manu, and Fabio grew up together on the mean streets of Marseilles where friendship means everything. They promised to stay true to one another. But now Ugo and Manu have been drawn into the criminal underworld of Europe's toughest, most violent and vibrant city. When Manu is murdered and Ugo returns to avenge his friend's death, only to be killed himself, it is left to the third in this trio, Detective Fabio Montale, to ensure justice is done. Despite warnings, Montale cannot forget the promise he once made Manu and Ugo. He s going to find their killer no matter the consequences.