Rich Niklas von Schermann and his wife Vivian leave to Berlin on urgent business for a few days, so they have cleaning lady Marie Wagner mind his villa and troublesome mother, senile widow Greta, whose nurse Reisch just made a crippling fall. Taking to the old lady, Greta even cancels the weekend her cop husband Dirk booked and volunteers to stay after the agreed weekend. Niklas's firm and marriage going bust, Greta supports him and flirts, but also insists on uncovering Greta's dark family secret, which shocks Niklas.