Monster is a biographical crime drama based on the life of Aileen Wuornos, a former prostitute who became a serial killer. The film explores Wuornos' troubled past, her relationship with a young woman named Selby, and the murders she committed. Charlize Theron delivers a transformative performance as Wuornos, earning her an Academy Award for Best Actress. Monster offers a harrowing portrayal of a complex and disturbed individual.