Romania, summer, 1925: An archeologist named Nazarie and an historian named Polanyi are guests of the widowed Mrs. Mosco, staying in her immense home as they carry out research in the region of the valleys of the Danube. Also living in the home are Mrs. Mosco's daughters, 30-year-old Sanda and 10-year-old Simina. A third prestigious guest, Egor, is a young artist in love with Sanda. During a period of suffocating heat, strange events are disturbing the guests in the villa. Caught in-between dream and reality, each of these events seem connected to the enigmatic persona of Christina, Mrs. Mosco's sister, who died mysteriously at a very young age.