Though no longer active as a feature film director, beginning in 1968 with his B&W debut sexplotation flick Her Private Hell (trailer) English director Norman J. Warren was a regular regurgitator of low budget British feculence, including such instant non-classics as the Bloody New Year (1987 / trailer), Terror (1978 / trailer) and Spaced Out (1979 / trailer). Today, he is primarily remembered for his notorious and still divisive sci-fi exploiter Inseminoid aka Horror Planet (1981 / trailer), one of the more disturbing cheap-and-sleazy Alien knock-offs ever made. But for awhile, alongside the much more productive English sleazemeister Peter Walker, Warren was a modernizer of the English film scene, a purveyor of (for their day) explicit, grim and bloody modern-day horror films, most of which have aged less gracefully than the Gothic period pieces offered by Hammer at that same time. But graceless or not, Warren's films do tend to offer a certain level of psychotronic entertainment alongside their oddly pleasing English accents – and in this regard, Alien Prey is no different.
According to imdb, Alien Prey was shot over ten days and, for the most part, written as it was shot. While both trivial tidbits are conceivable, the latter seems almost obvious, for the narrative often appears oddly spontaneous and under-developed, though neither of these "flaws" is quiet as evident as the lowliness of the film's probable budget. Nevertheless, the film has occasional exploitive interjections – the death of two policeman, a totally gratuitous topless sunbathing scene, the whole slow-motion drowning scene – that make one think that the given event or scene pictured was less planned or thought-out than simply added due to the scriptwriter's sudden realization that after a certain amount of dialogue some spice was needed again.
Featuring a core cast of three – supplemented by three other faces that are on screen mere minutes before they die – Alien Prey is basically a mildly bloody science fiction version of Mark Rydell's feature-film debut, The Fox (1967), which in turn is based on a novella by D. H. Lawrence. In The Fox, as in Alien Prey, the life of a lesbian couple living in seclusion is shaken by the arrival of a good-looking stranger. But whereas the stranger in The Fox is both earthly and earthy, the oddly distant stranger in Alien Prey is an alien in search of a reliable food source for his home planet. (That aspect of the plot could well have been inspired by the far more arty Nicolas Roeg flick, The Man Who Fell to Earth [1976 / trailer], in which the alien, played by David Bowie, comes to earth in search of water for his dehydrated home planet.)
Alien Prey was made in a day and age in which it was still daring if not totally mod to have a lesbian couple, but also a day and age in which the filmmakers were still not trendsetting enough to not make at least one of the scissor sisters a murdering psycho. In this case here, we have the innocent fem Jessica (Glory Annen of Felicity [1978 / trailer]), who gets to show her pert breasts occasionally, and her controlling lover Josephine (Sally Faulkner of The Body Stealers  and the unjustly under-appreciated Vampyres [1974 / trailer]), whom we learn over the course of the film is a nut-house escapee, confronted by a lightly somnambulant but not unattractive man named Anders (Barry Stokes of La corrupción de Chris Miller [1973 / scene]), who pukes whenever he eats greens, doesn't know what water is, and is quiet willing to both dress in drag and play hide-n-seek to celebrate the death of the fox supposedly responsible for killing chickens. His appearance drives Josephine to not only play with a huge switchblade – which really gave us switchblade envy, to say the least – but also to become all the more controlling, which is turn gives Jessica an itch that she thinks only Anders can scratch...
Disaster, of course, is inevitable, especially if you take into account that Anders sporadically changes into a fanged, doggie-nosed man that rips apart and eats the innards of animals and an occasional policeman. (One wonders why they didn't write in an Avon Lady or Jehovah's Witness to up the body count – but maybe they don't have them in England.)
Alien Prey is really not all that good of a film, but be that as it may it is also oddly mesmerizing. The cheapness of the production is apparent everywhere from the presentation of Anders' arrival to his final radio report, from the extremely limited location and number of actors to the cheesiness of the "gore" scenes. The acting itself cannot really be faulted, seeing that everyone is more or less a one-dimensional character, and the camerawork is functional if occasionally weak (the slow-motion drowning scene is a hilarious fiasco). The pace of the movie is positively languid, the occasional money shots – in a figurative sense, as this is not a porn movie – are far between and usually come across like an after-thought, and the ending is far less shocking than it is funny.
So why watch Alien Prey? Well, it's often rather amusing and everyone – including the aliens – all have nice English accents. And even if you are often left with the feeling that the filmmakers are trying too hard to be shockingly trendsetting – lesbianism, big phallic knife, alien in drag, the scene of kicking dead chickens and, of course, the heterosexual sex and meal scene and final ironic death – the oddities that the filmmakers throw in, as well as the low budget gleam, are strangely entertaining and endearing.
Still, considering all the film's pacing, be forewarned that despite all the engaging flaws of Alien Prey, if you watch the film too late at night it could well put you to sleep.