Police commander Simon Weiss, head of the division that supervises Paris’s demi-monde, starts out on his nightly tour of bars, discos and strip clubs, making sure once again that the owners don’t bend the rules too far. Weiss knows he’s between a rock and hard place: it’s obvious that criminal gangs run rampant in his special domain, and even more obvious that they’re protected by higher-ups in the department.

Chloé Saint-Laurent is a profiler and works with a police team to solve murders in Paris. She's very sweet, she wears very colored clothes and a huge yellow bag. She looks like a little girl who need a doll, but she's very smart and a very good profiler. Step by step, she fit in the team and her colleagues, very reserved at first, became her best friends.