Enigma for the Devil

The devil's greatest trick is to persuade us that he does not exist.

After the death of her father in Argentina, Elza returns to Brazil to visit her remaining family. While visiting her mother's grave, she takes a flower off an unknown grave and puts it in her mother's. Soon after that, she begins to receive strange phone calls from an unknown voice saying: "Give back my flower!". She becomes terrified and obsessed with the stranger's voice, and starts believing that it's the spirit of the deceased.