Monster is a biographical crime drama film based on the life of Aileen Wuornos, a notorious female serial killer. Charlize Theron delivers a transformative performance as Wuornos, portraying her troubled past and descent into a life of murder. The movie explores the psychological and emotional complexities of the character, shedding light on the factors that led to her violent crimes. Monster is a haunting and thought-provoking true crime movie that delves into the dark side of humanity.