The set of the secret underground laboratory in the film is one of the largest single sets.
Filming was delayed due to Elizabeth Sue’s torn Achilles tendon.
Sebastian's 3D model was donated to the scientific research department after the filming was completed.
The anesthesia gun used in the film is actually an early paintball gun.
The scene of Sebastian's brutal rape of his neighbor was later cut, because at the film screening, the audience thought it was too early for Sebastian to show his guilt in this way.
The film uses a pair of metal bones to create a sense of weight to carry the body.
Because of the dog-killing scenes in the film, director Paul Van Hoeven accepted an investigation by the American Association for the Prevention of Cruelty to Animals. In fact, the dead dog was a fake dog.
In order to arouse the real reaction of the actors, Paul Van Hoeven placed many speakers in different positions on the set, allowing the voice of the invisible man played by Kevin Bacon to appear in various positions.
In the film, the orangutan calls from the speakers are imitated by Paul Van Hoeven.
In order to use the film title, the producer bought the right to adapt the Dan Simmons novel of the same name, but the novel has nothing to do with the film.
In order to allow special effects technicians to remove themselves from the picture, Kevin Bacon is often painted green, blue or black, and he also wears contact lenses and wigs, covers his teeth and puts on tights.
