Doctor Malu lets her friend Sandra drag her along to a party - and meets the attractive and charming Hannes Jäger. Soon the two are inseparable. But a look behind the facade raises doubts: Hannes is pathologically jealous, follows her to work and shows up at her apartment. The relationship ends quickly - but the psychological terror is only just beginning: Hannes stalks Malu, entangles her in his lies, makes her seem untrustworthy and destroys her life piece by piece. How can Malu free herself from the stalker?