Roméo and Juliette are two young actors. They fall in love at first sight, move in together and make a baby. A love story and the founding of a home like millions of others. Except that their little boy, Adam, behaves abnormally. The young parents try hard to persuade themselves that everything is okay but, with the passing of time, they cannot delude themselves anymore : their son has a problem. Their fears are unfortunately confirmed : Adam suffers from a malignant brain tumor. From now on, war is declared. A war against illness. A war against Death. A war against despair.

In the small bordertown of Villefranche, lost in the heart of a large forest, crime rate is six times higher than elsewhere in the area. Each new crime Major Laurène Weiss solves with the help of her unusual team makes her sink deeper and deeper into secrets of the area.