HBO Nordic's first original series from Norway, Beforeigners is about two persons who mysteriously appear in Oslo. They are the first of many from the past to seek refuge in present time. Seven years later the community is transformed.

A few years after people from the past inexplicably began appearing in the ocean, Alfhildr - who comes from the Viking Age - is teamed up with burned-out Oslo police officer Lars Haaland as part of the police department's integration program. While investigating the murder of a woman with Stone Age tattoos, Lars and Alfhildr make some chilling, unexpected discoveries.

A new phenomenon starts happening all over the world. Powerful flashes of light occur in the ocean, and people from the past appear from three time periods; the stone age, the Viking age, and the late 1800s. No one understands how this is possible, and the people from the past, called beforeigners, have no memory of what's transpired. Some years later, detective Lars Haaland is teamed up with Alfhildr Enginnsdottir, the first police officer with Viking origin, to solve a mysterious murder.