Darkness: Those Who Kill Lost: Those Who Kill

Louise is determined to continue working as a profiler and when a couple is found brutally murdered, she takes on the case. She assists Detective Inspector Frederik Havgaard, who believes he knows who the killer is.

Louise locates Bjørn’s little sister Maria. Maria's caseworker suggests that Louise mentor the young woman, who is faced with the prospect of having her child taken away from her. Meanwhile, Bjørn is in hiding.

The police hunt for Bjørn is intensified. Following a search of Pelle’s home, Frederik and Louise uncover truths about Bjørn’s past, and a decision is reached on the forced removal of Maria’s child.

Another crime is committed. Frederik is convinced that Bjørn is the perpetrator, but Louise's investigations point to a different suspect. Bjørn turns to Louise and shares a secret with her that might close the case.

Three years on, Louise has moved to Aarhus to make a fresh start, but the past catches up with her when she meets Frederik again. He involves her in a new case in which a disabled woman has been found dead. Frederik thinks she was murdered, and the ensuing investigation seems to suggest that the dead body is a part of a larger pattern.

Louise and Frederik discover a connection between Bjørn and Alberte, who both grew up in the Breidablik commune. Louise visits the commune undercover in order to assist the police in their investigation and quickly notices the charismatic leader, Jon, who has a special relationship with Alberte.

Louise tries to get closer to Jon. Alberte becomes jealous and challenges Louise’s cover story. Meanwhile, Frederik discovers that one of Jon's old friends, who also owned Breidablik, perished in a mysterious fire.

Louise and Frederik put pressure on Jon to accept responsibility for his actions, but once again he takes advantage of his relationship with Alberte. Louise decides to confront the past.