Vom Ende der Eiszeit.

Police officer Lena Jörning is confronted with the first corpse of her professional career and recognizes her sister, whom she has not heard from for 12 years. The case raises many questions: When did Evelyn return? What roles do Evelyn's husband Claas and Lena's fiancé Bruno play in the death? The criminal investigation team arrives to take over the case. The investigation becomes a dramatic journey into the past for everyone involved, which - until then unrecognizable to Lena - overshadows even the present of the entire village.