Trivia: Jeff East, who plays teenage Clark Kent, was dubbed over with Christopher Reeves' voice. The only time Jeff's actual voice is heard is when he shouts in excitement after jumping past the speeding train.
Trivia: In the opening title sequence we see a garbage truck going through the Golden Gate Bridge toll booth. We would find out later that these trucks were used to transport the pods. The truck is traveling southbound from Marin County into San Francisco which is appropriate, (intentional or not) since the book Body Snatcher was set in Mill Valley, in Marin County, about 10 miles from the bridge.
Trivia: In this film Gregory Peck is attacked by large vicious dogs, dogs that can be trained to attack and kill; and in the film "The Omen", again Gregory Peck is attacked by very (or the same) vicious dogs.
Trivia: Sandy Duncan has a fear of real cats, so fake cats had to be used when she handles Jake in the film.
Trivia: Dick Miller plays the Mayor Buck Gardner, who serves much the same plot purpose as the Mayor Larry Vaughn in the first two JAWS films, in that he insists on keeping the beaches open and dismisses all danger signs. Dick Miller would go on to appear in every single movie ever directed by Joe Dante, right up until Miller's death in 2019.
Trivia: Despite receiving prominent billing, Jose Ferrer has less than three minutes of screen time.