In the film,"8mm," private investigator Tom Welles (Nicolas Cage) is hired by an old
woman named Mrs. Christian (Myra Carter) and her lawyer, Daniel Longdale (Anthony Heald), to determine if an 8mm film owned by her rich, deceased husband, is authentic and depicts the actual
murder of a teenage girl.
The girl in the film is the subject of the story and provides clues that enable Tom to focus on the origin of the girl's alleged murder.
order to conduct a successful investigation, Tom must identity the teenage girl and discover how she came to star in the film.