ट्रिविया

The dogs who attack the undisguised aliens near the end of the film were initially too scared to approach the costumed actors. The dogs were then acclimated to the presence of the suited actors - perhaps too well, for when the time came to shoot the scene of the dogs attacking the aliens, the dogs didn't attack the aliens, but jumped playfully around and on them instead. The dogs were then trained to go for the "breathing tubes" on the alien costumes. Apparently, the actors playing the aliens had to guide the dogs to attack the "breathing tubes."

The visual effects (absorbing cloud, glowing costumes, transformations, ray gun beams, etc) were created and developed by John P. Fulton, a pioneer in matte photography and trick shots. He brought to life "The Invisible Man" in 1933 but his most famous cinematic achievement is the iconic parting of the Red Sea in Cecil B. De Mille's 1956 epic "The Ten Commandments" for which Fulton won the Oscar for Best Special Effects just before he began working on this film.

This was an in-house Paramount production. It was intended to be released at the top of a pre-packaged double feature. Paramount had acquired a negative pickup of a low budget independent production, that had the benefit of being in color, to fill out the bottom of the double feature. In test screenings and early releases, it was discovered that there was more audience interest in the second feature. As a result, the second feature was given more of the promotional budget and made the leading feature. The original second feature, "The Blob" (1958) has become an icon of low budget 1950s science fiction while this feature has become almost forgotten today.

The house used for the exterior of Marge and Bill's home was located at 4946 Melrose Hill St. in Los Angeles. This same home was seen in the film Halloween H20 (1998).

Near the end of the film, the aliens' hand weapon looks remarkably like the one the Klingons used on the original Star Trek (1966), with a shorter barrel.