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.
Lt Bach's former boss and mentor Cat Meyer is in town to give evidence at a trial. 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.