Director Wes Craven and screenwriter Bruce Joel Rubin's original vision for the film was a PG-rated supernatural science fiction thriller, with the primary focus being on the macabre love story between Paul and Samantha, as well as a secondary focus on the adults around them and how they are truly monsters inside themselves. Craven filmed this version of the film and Warner Bros. decided to screen it to a test audience mostly consisting of Craven's fans. The response from fans was negative, criticizing the lack of violence and gore seen in Craven's previous films. The studio eventually discovered Craven's popularity as a horror film director. The president of Warner Bros. at the time, Mark Canton, demanded Rubin write six additional gore scenes into his script, each bloodier than the last. Rubin worked very hard with Craven to create a very deep and heartfelt movie out of it. Unfortunately, added gore scenes, re-shoots and post production re-editing of the movie heavily changed the original story. Craven and Rubin expressed strong anger at the studio and thus disowned the film.
Kristy Swanson said that she had probably thrown the basketball over a hundred times during the re-shoot filming of Elvira's death scene: Wes Craven kept at me to throw it as hard as I could to indicate great speed. I must have tossed that ball a hundred times. My arm sure felt I did." Swanson also said in an interview with Maxim magazine in May 2000 that the fake head was stuffed with actual cow brains that the production crew picked up from a butcher shop.
Kristy Swanson was 16 years old during filming, making 'Deadly Friend' her feature film debut. She thought it was very challenging to play a vibrant teenager re-animated as a zombie with a robotic brain. Today, Swanson is proud of her work in the film.
The B.B. robot cost over $20,000 to build. Wes Craven used a company called Robotics 21. His eyes were constructed from two 1950 camera lenses, a garage remote control unit, and a radio antenna taken from a Corvette. B.B. could actually lift 750 pounds in weight.
In promotional interview (Fangoria #60, The Prettiest Deadly Friend), Kristy Swanson mentioned some problems she had during filming: "I felt that, at times, people on the set thought I was just this dumb teenager who had to be led around by the hand. Nobody actually patted me on the head or anything like that, but I had a hard time getting the point across that even though I may have been young, I was a young actress." Wes Craven at first wasn't convinced that she could handle the role of Samantha: "Eventually, he changed his mind. He was always encouraging me, prodding me in subtle ways to get me to give a scene everything I could. There were days when we were behind schedule, or a particular scene was not working, where he would get a little upset, but I found Wes Craven to be a very patient man."