Duello is the story of Mariella De Rose, an orphan from Palermo, Sicily. When she was a kid, she was adopted by Bianca De Rose. Mariella moves to live in Rome and enters Sapienza University. Her main goal is to find out who her biological parents are. Going through various events and experiences, she begins to realize the limits of life. All of the characters in Duello resolves difficulties. Religion is based on holiness, but this story illustrates that even a virtuous man struggles, but this story illustrates that even a virtuous man struggles with this concept.