This film was based on the real life events of two teenage girls in 1983 who killed an elderly woman in Auburn, California after they had just met for the first time at school and cut classes to go on a irresponsible spree leading up to the murder... all over the course of one afternoon.
Fun was originally a one-act play written by James Bosley, and performed in a small theater in Los Angeles. The story was unique in that it was told in a very, cinematic way, mostly through the use of subjective flashbacks. The play was seen by Polish-born film director Rafal Zielinski and his partner, producer James R. Zatolokin. Both were extremely impressed with the play's brutal yet haunting quality. A little over a year later, Fun became a motion picture, directed by Zielinski and produced by the team's company, Neo Modern Films.
Producer James Zatolokin said they originally wanted Drew Barrymore, but it was difficult dealing with her agent, who was playing hard-to-get. After a few months of negotiating, they gave up and decided to make the movie without any real names.
They didn't have a special effects person for the scene where the girls murder the old woman. So the makeup woman just improvised by filling balloons with red water and paint, and then she put them underneath the old woman's nightgown. Alicia Witt pierced the balloons using a retractable knife during close ups. It was a very low-budget way of doing the scene, but it worked on screen.
At one point,Hillary (Renne Humphrey)bonds with prison therapist Jane(Leslie Hope) by rubbing her neck and shoulders.Humphery was actually massaging her co-star,and Hope was enjoying it so much that Humphery continued even after the scene was done fliming