While Diane Ladd appears in this movie, her daughter, Laura Dern appeared in another dinosaur film, Jurassic Park (1993). Ladd admitted she didn't think the script was very good and initially turned it down, until her old friend Roger Corman sent her a check with enough zeroes on it. Clint Howard's niece, Bryce Dallas Howard later starred in one of the Jurassic Park sequel, Jurassic World (2015).
On an $850,000 budget, principal photography lasted 18 days.
Original author John Brosnan (who wrote the book under the pseudonym Harry Adam Knight) was first approached to write the screenplay in mid-1991 by Roger Corman's wife Julie Corman, who formalized the deal at Brosnan's drinking club, and drew up the contract on a bar napkin. As the film was meant to compete with Jurassic Park (1993), Brosnan later wrote that he was taken aback when it was revealed that the film's budget would have only been $1 million. Although concerned that the restrictive budget would require a reduction in the amount of dinosaurs used, Corman assured him that he was free to write whatever he wanted, and that any modifications would be made in the final draft. Once Brosnan sent his first draft to Hollywood, he lost all contact with the film crew. His screenplay had in fact been heavily revised to the point where his credit had been reduced to "original story".
The Tyrannosaurus Rex effects were achieved by means of a miniature remote-controlled puppet, a man in a suit, and a full-sized, 16-foot-tall robot. However, only a handful of shots involved the full-size robot, which had too narrow a range of movements to be convincing. The man in the suit proved equally cumbersome and was scrapped. Thus, most F/X shots were accomplished with the remote-control miniature and even some hand puppets.
The movie bears little resemblance to the original 1984 novel by Harry Adam Knight, the pseudonym for Australian author John Brosnan. The book is set in England and is about a reporter investigating a strange series of brutal deaths which seem to be caused by a wild animal, but is in fact dinosaurs that have been brought back from extinction by an eccentric lord. The book features much carnage caused by many more dinosaurs than the film adaptation, such as a Deinonychus, Megalosaurus, Tarbosaurus, Plesiosaur, Dilophosaurus, Altispinax, Scolosaurus, Tarbosaurus, Deinonychus, Tyrannosaurus, and Brachiosaurus.