Sam Montgomery is a fictional character from the 2010 movie A Cinderella Story: Once Upon a Song. She is portrayed by actress Lucy Hale and is known for her passion for music and her dreams of becoming a singer. Sam faces challenges in her life, including a difficult home situation and the pressures of high school. In the film, Sam navigates her relationships with friends and family while trying to find her voice. The story highlights themes of self-discovery, perseverance, and the importance of following one's dreams, making it a modern twist on the classic Cinderella tale.