A woman is suspected of murder after her husband's death; their half-blind son faces a moral dilemma as the main witness.

D'Artagnan is forced to join forces with Milady to save Constance, who was kidnapped before his eyes. But as war is declared and Athos, Porthos and Aramis have already joined the front, a secret from the past shatters old alliances.

Young and ambitious Captain Vivés has just been appointed group leader at the Grenoble Criminal Squad when Clara's murder case lands on his desk. Vivés and his team investigate Clara's complex life and relations, but what starts as a professional and methodical immersion into the victim's life soon turns into a haunting obsession.