FBI consultant Thomas Adam receives a parcel containing a small statue. Touching it, he realises that his brother Eric, a police detective in Aix-en-Provence, is in danger and rushes back to France.
Thomas is shocked to find out from Eric's colleague Lena Ortiz that the bullet used in the attack on his brother comes from the same weapon that was employed to kill his parents 15 years earlier
Thomas is engaged to work as a consultant beside Eric and his police team. A woman returns home to make a horrific discovery: her husband has been murdered and the killer has left a gruesome scene.
A ghost from Thomas's past reappears, but he must focus on solving the case of a young woman who dies after being poisoned. The victim had a photo ID card, but could it be a case of mistaken identity?
Thomas is introduced to his haughty but brilliant new colleague Louise. The body of a young woman who has been stabbed is discovered by a lake. In the victim's arms is a baby, alive and kicking.
Louise is furious when she discovers that Thomas and Eric have ignored her instructions. A car accident leaves the driver unconscious and the passenger dead - but was he killed before the crash?
When a man collapses and dies in front of a church, his torso is found to be covered with fresh and distinctive tattoos created with poisoned ink. Thomas and Eric must delve into the victim's past.
When a family move into a renovated house, they discover the corpse of a man buried within a wall. A necklace is found during the investigation that belonged to a woman who vanished 14 years earlier.