Gamache ignores his superior's orders and investigates the disappearance of Blue Two-Rivers. As punishment, he's dispatched to the remote village of Three Pines to solve the murder of a wealthy socialite with no shortage of suspects.

Gamache looks into the victim's enigmatic past and learns one of the villagers withheld information. Gamache's delight at a breakthrough in the Blue Two-Rivers case is short-lived when the family has doubts, leading to a desperate act.

Gamache returns to investigate the disappearance of a popular resident but it soon becomes a murder case. Meanwhile, Lacoste discovers a key piece of evidence has been faked, and with Gamache's encouragement secretly reopens the case.

The villagers confront the truth of their past and exorcise their collective demons as Gamache makes a breakthrough and realizes Marc's killer had a very personal motive.

Gamache's anniversary celebrations at the Manoir Belleforet hotel are cut short by the discovery of a body; Gamache and his team investigate the case, which focuses on the hotel's owners, the dysfunctional Morrow family.

Gamache is certain he is closing in on solving the mystery of Julia's murder; Kevin and Lacoste have a tense encounter as Kevin tries to defend himself, saying he was framed for murder.

When a man bent on vengeance is discovered in the woods near Three Pines, seemingly the victim of a group lynching, Gamache finds himself wondering whether all the villagers are capable of murder.

Gamache and his team unearth a tragic story that provides the key to the victim's desire for vengeance and by doing so leads the team to his murderers.