Development While director Harry Bromley Davenport admits an affinity for the sci-fi genre, his return to the
Xtro franchise itself was due to the difficulty of getting new projects off the ground, and the brand's recognition with investors. It was the Briton's first shoot in the U.S., which required minor adjustments on his part even though it was a non-union production. Bromley Davenport met
Xtro 3 actor and screenwriter Daryl Haney through a mutual acquaintance at
Roger Corman's Concorde, Haney's frequent employer. The pitch agreed upon by both men was "
The Dirty Dozen meets
Predator", although they were conscious to build on that with original motivations for the alien. In the script, the creature was seldom described, but was not a humanoid. However, the director opted to give it a more relatable shape so that it could elicit empathy from the audience. During writing, Haney knew that he would act in the film, but did not know which role he would be given.
Special and visual effects Supervisor Paul Sammon and his company Awesome Productions were given five weeks to create the visual effects. Based on the script, only 16 effect shots were projected, but as the shoot went on, Bromley Davenport gained confidence and their number grew to 41. While it would have been cheaper, the director refused to use a man inside a suit, which he felt would not have worked for the expressive creature he wanted. The story's island was primarily represented by the
Iverson Movie Ranch in
Chatsworth, with additional location work done at the Pölsa Rosa Ranch in
Acton. The sets, such as the inside of the bunker inhabited by The Survivor, were built inside a warehouse in
Burbank. Some further footage was also captured on boats off the coast. Paul Sammon and Andrew Divoff suffered cuts to their hands while filming at sea, while Virgil Frye's leg was injured by a
squib and Sal Landi hurt his back. ==Release==