After taking several years off to have children, nurse Clara Horn returns to work and begins to feel the effects of the much tougher daily routine at the clinic - pressure, stress and tension are the order of the day. But she soon realizes that there is much more going on in her clinic: Apparently, one of her colleagues is deliberately killing patients. Clara must overcome not only her own doubts, but also massive resistance among her colleagues in order to convict the perpetrator, Rico Weber.