When Léo's brother Ludo is killed in Hamburg, despite orders she partners with German cop Mélanie to investigate. Unbeknownst to them, Nice faces a threat and they share an unknown connection.
The intrepid Léo, self-proclaimed "best cop on the Riviera", learns that her colleague and brother Ludo has been killed in Hamburg. While she wants to discover the truth, she is forced by her superior to let a German supercop do it. There is no question of letting a "shame in a suit" investigate, especially when she discovers that it is, in fact, attractive and highly-trained Mélanie. Forced to team up, these two women with characters as explosive as they are opposite have no idea that Nice is facing an imminent threat and that they share an unimagined link.
A French cop is trying to find her colleague, Ludo. He's been missing for 10 days. It seems this French cop, Leo (Alice Taglioni), is the only one who cares about Ludo's whereabouts, because her boss Hernandez (Noemie Lvovsky) is completely disinterested. Additionally, there's a fancy climate summit happening in Nice that she's more worried about. A popular young climate activist Sima Scott is also attending the summit and there is pressure on the police to have air-tight security for the event. Sima has been getting death threats, and about 100 oil and energy CEOs are also expected to attend. The venue itself is very difficult to secure.
However, a little while later, they get the news that Ludo has returned from Hamburg, Germany, and is at the airport. When they get there though, it seems like Leo's hunch was right and Ludo's come home in a box. But, more importantly, they can't do anything about it at that moment because the German police are desperate to figure out what happened to him, and only after the case is solved can they give him a proper official funeral. Earlier, Leo got a guy named Bat (Baptiste Lecaplain), an ex-hacker, to help her look for Ludo. Bat's kind of a stupid guy, but he's helpful, and soon enough, Leo falls for him.
Leo knows that a German cop's coming to Nice to solve the case, but she wants to get on it before the guy arrives. Shockingly, when she goes to Ludo's house, the cop she finds is a woman who can speak French and is way more qualified than the image she had in her head for whoever would be solving the case. Melanie (Stefi Celma) happens to be Ludo's girlfriend. Ludo had proposed to her, and she came to Nice to figure out what happened to him.At first Leo wants to get Melanie off the case and sends her to Bauer (Jess Liaudin) indicating that he has a tip for the case. Bauer only hated Leo and attacked Melanie. Melanie takes a few hits but ends up beating Bauer in a fight.
Leo speaks to her uncle Mamich (Antoine Dulery) to find what Ludo could have been doing in Hamburg.Melanie reveals to Hernandez and Leo that she is a cop in Germany but lived in Paris for a large part of her life. Melanie says that Bauer admitted that Ludo was looking into a real estate mogul named Cassati. Cassti is a major sponsor of the climate summit and a respected figure in Nice.Melanie gets invited to Cassati's party and collects a fine powder from one of the rooms. When tested in the labs, it is full of explosive chemicals.Now, seeing as they both have one end goal, Melanie and Leo team up to solve the case.
Hernandez had assigned Laura (Delphine Baril) & Gustavo to investigate Ludo's death. But Laura was working for Cassati, a criminal who wanted cops to look the other way while he brought a shipment into Nice. Laura are Gustavo are not corrupt, but dumb enough not to understand that Cassati was using them.
Bat hacks into Cassati's accounts and finds suspicious transactions to an offshore account. This prompts the girls to visit Cassati's home with Bat. As they arrive, they see 2 assassins shoot their way into Cassati's villa and follow them in. In the ensuing shootout Cassati is killed when a chandelier is shot and fall on top of him.The assassins escape.Melanie and Bat track down the assassins to a man named Zako, who lives in Hamburg. They also find that one of Zako's men Caesar has just opened a garage shop in Nice.
Ludo went to Hamburg because he learned of a package that was getting delivered to Nice. This package is a bomb and this exchange is supposed to happen between a man named Zako (Virgile Bramly) from Germany and a man named Cassati (Lucien Jean-Baptiste) from France. Cassati's basically doing the delivery job for a big player.Ludo figured out there was some sort of foul play and tracked down Zako. Zako's girlfriend Kim (Katrina Durden) is a sniper with perfect aim, and she's the one who killed Ludo, while he was trying to figure out what was going on.With Bat's help, Leo and Melanie make the connection to Cassati and try to get him to spill the beans. In the middle of all of this, Leo gets suspended for trying to solve Ludo's case, and Melanie is found out (She is not a cop from Germany but is a cop in Paris, and only Ludo's girlfriend. As the real inspector from Germany showed up in Hernandez's office), but they still keep at it because they're determined to bring Ludo justice.
There's a young girl named Sima (Kay Sibal) at the climate summit, and she's going to be visiting Nice to speak about climate and the overuse of fossil fuels. Her right-hand man, i.e., the guy who is supposed to look after her safety and make sure she gets from place to place, is Fredric Valence (Franz Lang). He looks after her communications, but it seems like he also wants her dead.So, the package that Cassati was trying to bring in was for Valence, and it's a bomb that's meant to kill Sima. Zako delivers the bomb to Valence and Kim goes with Valence.Bat was in the garage and saw everything but was seen by Zako. Melanie and Leo arrive to save Bat. Before Zako could reveal anything, he and his men are killed by Kim. Bat manages to get hold of Zak's communication device and determines the location of the numbers he was calling. They find that the location was the summit.Bat figures out that Valence got payments from Petro Global, and that he is getting paid by the oil companies to kill Sima.
Melanie gets into the summit but is captured by Kim and taken to the yacht.
Eventually, the ladies get the sniper, Kim, arrested by recording her threatening Melanie and make sure Valence is caught too. At the summit, Laura tells Gustavo that she cannot work for criminals and confesses to Melanie and Leo.
Only the bomb is still in the car, and Sima's in the same car. Melanie, Leo, and Bat are the only ones who can fix this too, and after they get Sima out of the car, they drive it into the sea so that nobody's life is threatened.In the last moment, Bat thinks he's figured out how to disable the bomb through his iPad, but he hasn't done it, so they all end up jumping into the sea. Just before that, Leo admits that she's in love with Bat and that Melanie's the best friend she's ever had. Bat reciprocates her feelings as they swim to the shore, and Melanie smiles as she watches over them.
The police hold a funeral for Ludo, and as Leo hugs Melanie, so does everybody present there, making a big circle of white caps. Ultimately, Ludo was loved and important, and it was sad for him to go the way he did. However, at least in this sad situation, Melanie and Leo met and became best friends, probably just as Ludo would've hoped for. Bat also has his wish come true because he joins the force, and their next step is to get Cassati to talk. Melanie and Leo are driving off into the Riviera together, all smiling.
