According to a magazine article the "bubble" effect seen when the audience is seeing things from the alien's POV was achieved by actually blowing a specially formulated "tough" bubble around the camera lens. These shots were kept short since the bubbles only lasted a brief time.
Although credited to Harry Essex, most of the script, including dialogue, is copied almost verbatim from Ray Bradbury's initial film treatment.
Fantastic Something, a Hellenic pop duo with a minor UK hit in 1983 (If She Doesn't Smile), adopted their name from a line heard in the movie ("That fantastic something!")
In a separately filmed trailer, Richard Carlson talks to the audience about the film and about Three Dimension; animated sequences attempt to illustrate the three dimensional effect.
The Universal make-up department submitted two alien designs for consideration by the studio executives. The design that was rejected was saved and then later used as the Mutant in Universal's This Island Earth.
This was one of the few American movies from the 1950s to place its credits at the end rather than at the beginning.