In a small village in Turkey, a Greek family with three daughters lives in a house near the mountains. Even though the girls father warns them to stay away from the mountains because of evil spirits, the youngest one ignores his wishes and one day heads deep into the mountains. Suddenly, she is covered by a cloud of green mist, feels something enter her soul, and faints. She will never be the same. As the young daughter develops into a beautiful young lady, her evil thoughts begin to take over. After her parents and both her sisters die, she is left to care for her niece. Unfortunately, she attempts to control her nieces destiny but fails, and eventually the girl immigrates to America with her husband and son, Spiro. The mother gives birth to a daughter, Maria, and then two years later, to another daughter name Eva. Two years later another child came into their lives and named her Cathy after the aunt who raised her mother. Cathy is possessed with her aunts evil spirit. As her parents try to protect her and make excuses for her malicious behavior, Spiro is wise to her evil thoughts and finds an escape in the military. Now Cathy has but one person to invoke her wrath uponher sister, Maria. The Impious Sister shares the frightening tale of the power of an evil curse as it travels through generations and across an ocean while wreaking havoc on one family.
