A dead dog covered in human blood leads police on a frantic hunt for a missing infant. Suspicion falls on the child's nanny, but Balthazar makes a different conclusion.

A collection of bones found in an old abandoned building yields 3 bodies dating back to the Middle Ages and one who died a week ago, partially dissolved in acid

A knife attack bears the marks of a serial killer who is supposedly in prison. Balthazar and Bach travel to a remote town in the mountains to look for a copycat.

When a woman is found hanged from a bridge it appears to be straightforward suicide, but Balthazar finds it strange that another victim died the same way days earlier..

Balthazar that determines that a body at a derelict toy store died from an accelerated version of the bubonic plague. Now exposed, he locks himself inside to stop its spread.

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

The corpse of a woman dressed as Snow White leads to the disappearance of 8 people and a sick game played out in the deepest French countryside.

Devastated by the failure of their investigation, Balthazar and the detectives try to focus on the deaths of three teenagers murdered while camping.

Lt Bach's former boss and mentor Cat Meyer is in town to give evidence at the trial of a young man accused of killing his sister. When Cat is found stabbed to death in the woods, Bach has step in but quickly discovers something is very wrong with the case.

When the Lise's killer sends Balthazar a video of his latest murder, Balthazar relies on drugs to numb the pain and starts to lose his grip on reality.