As the second season begins, the police are searching for a missing child, after they discover a dead dog with traces of human blood. Although the officers soon suspect the child’s nanny, Balthazar comes to a different conclusion.

Balthazar analyses bones discovered in an old building and finds three bodies dating back to the Middle Ages, and one recent victim partially dissolved in acid.

Balthazar and Bach travel to a remote mountain village when a husband and wife suffer a knife attack that bears the marks of a serial killer who is supposedly in prison.

When a woman is found hanging from a bridge, it appears to be straightforward suicide, but Balthazar finds it strange that another victim died the same way days earlier after using a blind-dating site.

Balthazar locks himself inside a derelict toy store after he examines a body and determines that the victim died from an accelerated version of the bubonic plague.

After hearing an emergency call from a distressed teenager, Bach arrives at a crime scene with an empty car with smashed windows and a trunk full of snakes.

After hearing an emergency call from a distressed teenager, Bach arrives at a crime scene with an empty car with smashed windows and a trunk full of snakes.

Balthazar and Bach finally track down a suspect in Lise's murder case, only to find he has been dead for 10 years and the real killer has been using the identity of the deceased; teenagers are butchered during a camping trip.

After receiving a threat from Lise's killer, Balthazar worries his new girlfriend, Maya, is in danger; Bach is called to investigate a body found in a pond, but the case turns personal when she realizes the victim is someone close to her.

Balthazar relies on drugs to numb the pain when Lise's killer sends him a video of her being murdered; a disturbed man wearing a woman's bloody scalp walks into the police station.

Devastated by the death of a friend, Balthazar has left his job in Paris and spent the past six months sailing around the Atlantic, vowing never to touch a corpse again. His resolve is tested when he discovers a dead body near a remote island.

While Balthazar is examining the body of a young man with Bach’s help, he is called to rescue a woman who has been brutally assaulted. Soon enough, though, he realizes that these seemingly unrelated cases share a surprising link.

Balthazar is speeding away, trying to escape from the army that is pursuing him. Helene and a wounded man are with him in his car. But what could have possibly happened in the last 48 hours that brought them to this exact moment?

The badly beaten body of a woman is discovered in a chapel and the DNA sample that Balthazar analyzes links her death to that of two other women in the past 12 months. Were these women truly the victims of a serial killer?

Balthazar is investigating the case of a man and a woman who were found in the forest brutally murdered. However, soon he finds himself in a world between fantasy and reality that will help him realize a great deal about his life.

A bloody-faced little boy turns up at a gas station and disappears just as fast. Raphael and Bach are sent to locate him, but their investigation brings them face to face with some shocking revelations and a recent murder case.

The body of a missing man is found in a balloon-covered pool and the crime bears the marks of a psychopath who has been escaping from the police for a while now. Meanwhile, Raphael gets one step closer to the truth about Lise.

In the shocking finale of season 3, Janvier manages to escape just as Balthazar prepares to have the happiest day of his life. But after everything he has been through, does he even still have the right to believe in happiness?