A young woman named Margherita B. works as a governess for a wealthy aristocratic family in a beautiful villa near Rome called “the glass house.” She is responsible for taking care of twin girls, Lucrezia and Lavinia, who seem perfect and talented. At first everything appears peaceful and elegant, but soon strange and terrifying events begin to happen. The girls talk about mysterious “others” who are connected to the house and its dark past. Margherita is slowly drawn into a disturbing and unclear reality, where it becomes difficult to understand what is real and what is imagination. The story explores fear, truth, and the human mind.