Police Chief Herville is found dead in a Chinese restaurant in the 13th arrondissement of Paris. Gilou must break the news to Laure, who is being treated in a police rehabilitation centre. Now in charge of the unit, Gilou begins investigating with new recruit Ali, who is fresh out of training. Meanwhile, Judge Roban returns to work from his time off sick only to find he is soon due to take compulsory retirement. And lawyer Joséphine struggles to adapt to life in prison while awaiting trial.

As the police identify that their top priority is to track down Ryan and his gang, Gilou agrees to work with Laure again, but she must find her place now that he and Ali are a team. Meanwhile, Edelman provides legal counsel to Joséphine to help her get out of prison.

Ryan is not telling the whole story, so Roban decides to lock him up. The banknotes recovered from the robbery lead police to take their investigation to a nearby housing estate. Meanwhile, a link is uncovered between Wang and Herville, and Joséphine builds a rapport with her cellmate, Lola.

Laure follows the drug traffickers’ courier to a warehouse in Aubervilliers, where the investigation suddenly acquires a new dimension. Meanwhile, still frail, she struggles to cope with the responsibilities in her personal life. Joséphine has a hearing with the judge. And Roban pursues a case of negligence at a hospital by involving the hospital director.

Police work to uncover the role of Ryan's elder brother Fouad in the money-laundering scheme. Beckriche calls on his former colleagues at the fraud squad to assist in the investigation, but his decision is controversial. Laure and Gilou make a breakthrough arrest, while Edelman presses for a crime scene reconstruction he thinks will help Joséphine.

The money-laundering operation closes ranks. Beckriche orders his team to let the fraud squad take the lead with their investigation, but will his colleagues comply? Out of prison, Joséphine finds herself trying to pick up the pieces of her personal and professional life.

Following the debacle resulting in Fouad's death, the team is taken off the investigation. Laure is increasingly concerned about Lebrion's interference, while Joséphine realises she also has reasons not to trust Edelman.

Roban falls into a trap set by Joséphine and Edelman, whose professional partnership is now, however, on the rocks. Laure and Gilou continue to work on the investigation they've officially been taken off, identifying a suspect who may have been involved in the money-laundering operation. Beckriche's loyalty to his former boss is put to the test.

With his role in the investigation irreparably tarnished, Roban loses his grip on the case. Laure and Gilou go ever further out on a limb with a rogue decision to reactivate the now-dormant money-laundering operation. Joséphine, who now works for Solignac, continues to set traps.

Laure and Gilou sink deeper into taking illegal measures, risking yet more grave repercussions. Their former team member Tintin is tasked with investigating their methods. Meanwhile, Joséphine does her best to protect Lola. However, she proves to be a most uncooperative defendant - for reasons that Joséphine understands only too well.

When Laure and Gilou, under investigation by Internal Affairs, are taken into custody, Tintin is torn between his loyalties to his former colleagues and his new job. Josephine also faces a moral decision about how best to fight Lola's case.

As police close in, Cann plans to make a run for it. But first, he reaches out to Edelman, asking for his help. Josephine intervenes in the investigation but is not immediately trusted. Meanwhile, Laure and Gilou still have not been cleared of wrongdoing by Internal Affairs.

The police make an appeal to the Press and get their hands on Elina's diary - which reveals she had friends in high places. Pierre discovers a connection between the murder victim and a childhood friend of his, now a wealthy businessman - and it seems they met the day before she died.

The police delve into the personal life of a businessman who burned to death in his own home, Clement struggles to conceal his friendship with a suspect in the Andrescu case, and Gilout's drug habit gets out of control. The mother of a murdered baby is accused of negligence.

A prominent ministerial adviser, who has links to prosecutor Pierre Clement's close friend Benoit Faye, joins the list of suspects for the ruthless killing of Elina Andrescu. Meanwhile, Captain Laure Berthaud comes up against lawyer Josephine Karlsson during an inquiry into a double murder.

The inquiry into Elina Andrescu's murder takes yet another disturbing turn when the body of her missing sister Sophia is found in a freezer. A distraught Ghislaine Androux is brought to trial in connection with the murder of her baby, but Judge Roban soon begins to regret meddling in the affair.

Pierre begins divorce proceedings after his estranged wife is implicated in a drug trafficking scandal. Josephine defends a man accused of committing brutal acts of torture, while Gilout's drug addiction tests Berthaud's patience

Pierre Clement unwittingly endangers Benoit Faye's life when he resolves to have his friend arrested in connection with the Andrescu case. Lawyer Josephine Karlsson is called in to defend a young man accused of rape, while Gilout is compromised by blackmailers.

With Benoit Faye in intensive care following an assassination attempt, the prosecution in the Andrescu case has lost its main witness. The events leading up to the sisters' double murder are reconstructed using Benoit's recollections.

DPJ group captain Laure Berthaud is responsible for investigating the case of a student blown apart by the bomb he was making. Soon he finds himself facing some far-left activists who advocate very radical urban guerrilla and direct targeting of police. Josephine Karlsson driven by her hatred of the police and government goes beyond her role as a lawyer and is trapped by the DCRI which monitors the far-left activists. Pierre Clément, who dreams of greater things, is wanted to defend Johnny Jorkal, a crime lord. Judge Roban, back to court after a long absence, finds he has been sidelined.

The Koné case takes a new turn with the destruction of a bank by a group of activists from the far-left. The lawyer Josephine Karlsson must come to the defense of Mary. but is retained by the team captain Laure Berthaud in the case of the student found dead, torn apart by a roadside bomb. Meanwhile, Josephine's associate, Pierre Clement, dreams of big business but having accepted crime lord Johnny Jorkal's request to defend him, he cannot help wondering why Jorkal has chosen him over someone more experienced. As for Gilou, he is approached by the nightclub owners who would like something done to resolve their problems with the authorities...

Berthaud and her team visit the scene of the immolation of a Kurdish detainee and spot Sophie Mazeret amongst the demonstrators outside the center.

Berthaud stakes out the Turkish restaurant that the Kurdish suicide victim was known to frequent and uncovers a work crew of illegal immigrants.

The autopsy of the Kurd reveals a hidden clue which leads Herville to upgrade the case to the highest priority. Special Branch try to blackmail Karlsson.

At a police meeting called when a youth is shot dead in a drive-by killing, Herville boasts that his unit will have arrests within 24 hours.