In the fourth season, a woman is found brutally murdered on a small artificial Danish island close to the Øresund Bridge. The woman is Margrethe Thormod, Thormod, Director General of the Migration Agency in Copenhagen, who was recently embroiled in a deportation scandal. Danish detective Henrik begins to investigate the murder without the involvement of Saga, due to the fact that she has now been imprisoned for the murder of her mother. Henrik is missing his colleague and wants to visit her as often as possible so she can help with the case. However, her predicament renders her unable to help. Henrik’s search for his missing daughters is also frustrated by Saga’s imprisonment and he gets close to giving up.

一名从乡下搬到奥斯陆展开大学新鲜人生活的挪威女孩席玛，单纯而天真的她，内心有着坚强的信仰与管教严格爸妈的谆谆教诲。在入学后，与非常美丽的同学安雅有着深厚友谊，但却在一次图书馆癫痫事件后，她开始发现自己...

身为保险公司调查员的麦斯，因为找寻失踪的客户，而意外发现一间隐密在深山的旅馆，专门以服务享受各种自杀幻想的顾客群为主。
而当他化名混入旅馆进行调查之后，才发现这间旅馆的经营另有蹊跷，唯一能离开的方式，只有真正的死亡……