When her brother is found murdered, Maren Adam’s orderly life goes off the rails. Though the police investigate, they can’t seem to find the killer.
But Maren can’t let go of her brother’s death. She launches an investigation of her own, and soon finds evidence pointing to a conspiracy of massive proportions. Is her brother the victim of a criminal organization involved in storing toxic waste in the old tunnel networks below Hamburg?
While Maren’s husband, Mehdi, and her kids, Paula and Daniel, try to return to normalcy, Maren gets sucked deeper into her research in order to find clues supporting her suspicions. But no one believes her, and the police seem to be following a false trail.
What ensues is conflict, misunderstanding and empty reassurances. Increasingly, Maren retreats from the others. More and more, she feels threatened and alone.
Far too late, Mehdi and Maren’s best friend, Iris, notice that it isn’t Maren who’s in danger, but that it’s Maren who is a danger to herself and her family. A full-blown catastrophe seems inevitable.