Bach is sure they've finally caught Lise's killer, a man named Janvier, but Balthazar doesn't believe it. When a woman is found beaten to death in a church, Balthazar thinks her murder is linked to a secret martial-arts club.

Flying high after asking Maya to move in with him, Balthazar accompanies Bach on the search for a wounded boy. When they arrive at the child's home, they find the house empty and his mother dead.