Maren Hilbert is the new teacher at the private elite school Sophienbund. She soon realizes that the school, which looks so perfect on the outside, is in a pretty bad state on the inside. When a killing spree is announced, Maren knows she has to act. But neither the principal nor her colleagues take the threatening emails or Maren seriously, only police officer Niklas Götz (39), the father of one of her pupils, supports her in her research. Maren is certain: the potential killer is a boy from her class and he is serious. A race against time begins.