Because of the immensely troubled production and disagreements with MGM, Douglas Trumbull opted never to direct a Hollywood film again. In 1983 he stated, "I have no interest . . . in doing another Hollywood feature film . . . Absolutely none. The movie business is so totally screwed-up that I just don't have the energy to invest three or four years in a feature film. Moviemaking is like waging war. It destroys your personal life, too. The people who can survive the process of making films have largely given up their personal lives in order to do that, just because it's such a battle to make a movie. And in doing that, they've isolated themselves from the very audience that they're trying to reach."
Lana Wood filled in for sister Natalie Wood in some shots to help finish the film, after Natalie's untimely death.
When Natalie Wood died near the end of principal photography, studio executives tried to kill the film and claim the insurance, saying that director Douglas Trumbull could not complete the film. However, Trumbull's contract gave that decision to him, and he insisted on completing it, using a stand-in and changing camera angles for the few remaining shots of Wood's character. The resulting hostility between Trumbull and the studio executives meant that this would be Trumbull's last Hollywood film. He has since devoted his efforts to effects work for IMAX films, theme park rides and the like.
Several scenes involving water were cut from the film after Natalie Wood's shocking death. In one scene, Wood's and Christopher Walken's characters jump in the pool at their North Carolina home. In another, during the original reconciliation sequence, their characters went out on a pond in canoes.
Douglas Trumbull originally wanted to film this movie in "Showscan," a 60-frame-per-second widescreen process he'd developed, but the costs of retrofitting theaters to show it proved prohibitive. If the "Showscan" version had been made, each non-"Brainstorm" frame would have been printed twice to create a 30-frame-per-second "normal" film rate to complement the cropped, non-widescreen shots. The intent was to create an experience similar to what the onscreen characters were "viewing."