Many real aspects of Columbine shooters Eric Harris and Dylan Klebold were used in the film. Most obviously being that the entire film was shot exclusively as a video diary (excluding the massacre itself), as Harris and Dylan did film many videos (later known as "The Basement Tapes") documenting their plan. As of April 2025, "The Basement Tapes" still have not been made available to the public.
Andre an Cal's parents were portrayed by Andre Keuck and Calvin Robertson's real parents. Director Ben Coccio wanted the movie to be as realistic and believable as possible.
No professional film cameras were used in the making of the film.
The party scene was filmed in Albany, New York during an actual party with many guests unaware of the filming. The location was the actual apartment of the director's brother, who portrays Chris in the film.
During the scene where Calvin and Andre go shooting with Chris, Andre says "Natural Selection" while Calvin is firing. "Natural Selection" was Eric Harris's (Columbine shooter) favourite law. basically, it states that nature gets rid of the weak organisms, while supplying the stronger organisms.