Monster is a 2003 crime drama film about serial killer Aileen Wuornos, a former prostitute who was executed in Florida in 2002 for killing six men (she was not tried for a seventh murder) in the late 1980s and early 1990s. Wuornos was played by Charlize Theron, and her fictionalized lover, Selby Wall (based on Wuornos' real-life girlfriend Tyria Moore), was played by Christina Ricci. Patty Jenkins wrote and directed the film.

Theron received critical acclaim and won seventeen awards for her portrayal, including the Academy Award for Best Actress, Golden Globe Award for Best Actress and the Screen Actors Guild Awards for Outstanding Lead Actress.

Plot After moving from Michigan to Florida, Aileen Wuornos, a prostitute, met Selby Wall in a gay bar. After she was initially hostile and declared that she was not gay, Aileen talked to Selby over beers. Selby took to Aileen almost immediately, as she liked that she was very protective of her. Selby invited her to spend the night with her. They returned to the house where Selby was staying (temporarily exiled by her parents following the accusation from another girl that Selby tried to kiss her). They later agreed to meet at a roller skating rink, and they kissed for the first time. Aileen and Selby fell in love, but they had nowhere to go, so Selby went back to her aunt's home.

After being raped and brutalized by a client, Vincent Corey, Aileen killed him in self-defense and decided to quit prostitution. She confessed her action to Selby, while Selby had been angry with her for not supporting the two of them. Aileen tried to find legitimate work; but because of her lack of qualifications and criminal history, prospective employers rejected her and were occasionally openly hostile. Desperate for money, she returned to prostitution. She robbed and killed her johns, each killed in a more brutal way than the last, as she was convinced that they were all trying to rape her. She spared one man out of pity when he admitted he has never had sex with a prostitute but eventually killed another man who, instead of exploiting her, offered help. Aileen used the money she stole from her victims to indulge herself and Selby.

However, as Selby read in the papers about the string of murders, she began to suspect that Aileen may have committed them. She confronted Aileen, who justified her actions by claiming she had only been protecting herself. Horrified, Selby returned to Ohio on a charter bus. Aileen was eventually arrested at a biker bar and spoke to Selby one last time while in jail. Selby revealed some incriminating information over the telephone and Aileen realized that the police were listening in. To protect her lover, Aileen admitted she committed the murders alone. During Aileen's trial, Selby testified against her. Aileen was convicted and sentenced to death. On October 9, 2002, Aileen was executed by lethal injection.

https://en.wikipedia.org/wiki/Monster_(2003_film)