A unconscious woman with severe head injuries found near Heidelberg poses a mystery for the police: Who is she? And why is no one looking for her? When she wakes up, it turns out that she cannot speak. Chief Inspector Alexander Gerlach practices patience, but then there are further murder attempts on the stranger. It is only when the body of a man from Angola appears that Gerlach begins to sense the true connections, and a dangerous race against time begins.