Cohle and Hart travel around trying to track down leads to their case. Darker sides of Hart's personal and family lives are revealed.

Cohle and Martin finally get a new wind in the case and can confirm a suspect. Martin's mistress gets on with somebody else leaving him furious. Cohle's theory becomes increasingly more convincing than ever.

Martin is faced with marital problems. The search for Reggie Ledoux leads the detectives to a motorcycle gang called the Iron Crusaders, which Rust worked undercover in the past.

Hart and Cohle share the spoils of a solved case; Papania and Gilbough confront the detectives with troubling new intelligence.

Cohle's activities in 2002, when his partnership with Hart disintegrated and he quit the force, are recalled by Maggie.

Cohle and Hart try to discover if a series of missing persons reports could be related to the Dora Lange murder and the Tuttle family.

An overlooked detail provides Hart and Cohle with an important new lead in their 17-year-old case.