Prey (1977)
Prey (aka Alien Prey) is a British science fiction horror film from 1977 produced by Terry Marcel and directed by Norman J. Warren. Starring Barry Stokes, Glory Annen and Sally Faulkner.
Plot
Jessica awakens when an alien spacecraft lands nearby. 
After killing a young couple, the alien assumes the identity of the recently killed young man. 
Jessica and her possessive lover Josephine invite “Anders” in when it appears he’s hurt. 
Soon Jessica becomes suspicious of Josephine’s overbearing ways, and relies more on the alien for support, but his purpose on earth remains unclear.
Notable scenes
The cannibal scene.
Making of Prey
In order to film in the lake where Anders was rescued by the two girls, the actors had to have injections as the dirty water was a dumping ground.
The principal cast members wore their own clothes.
The majority of this film was shot with a hand-held camera.
Originally rated X when first released in the U.K.
The cast and crew lived out of the sprawling country house that the film takes place at during the production.
The trailer for Prey features some footage not used in the final cut of the film. Among the clips is POV shots of Anderson running through the woods, a scene of Jessica walking by a skeletal hand partially buried in the ground, and a shot of a shirtless Barry Stokes standing in the woods.
Animal parts from a butcher shop where used for the bloody carnage of the movie’s climax. These had to be frozen before shooting, much to the shock and surprise of the actors who had to have the freezing guts applied to their nude bodies.
At the time of filming, star Sally Faulkner had never fired a rifle before. When she had to shoot one for the fox hunting scene she was stunned by the kick back of the powerful gun.
The contacts that Barry Stokes had to wear on his eyes during the movie were quite painful and he could not see with them on.
The infamous “drowning” scene was shot in slow motion so the cast wouldn’t have to spend extended time in the waters of the stagnated pond. The makers loved the look of the footage afterward and left it unedited.
Director Norman J. Warren agreed to do the film based on the premise alone. When the production was mounted it had no completed script; the writer would have to rush out material to the cast daily during shooting.
The parrot that played “Wally” vanished during filming and was never seen again.
Due to the script being written as they filmed, certain scenes were partly or wholly improvised. One example is the lesbian sex scene between characters Jessica and Jo (Glory Annen and Sally Faulkner), which was added mainly to boost the film’s overseas distribution prospects. Faulkner had performed nude before so she was onboard with the scene, but Annen had not. She was very hesitant at first, but finally agreed. Once filming began, she relaxed and really got into the sex scene. As a result of her being nude in this film, all the offers she started receiving afterward also required full nudity, including Felicity (1978) and Spaced Out (1979), also directed by Warren.
To reduce costs, no alien spacecraft is seen at the start of the film. Instead, Kator’s arrival is conveyed solely by flashing lights and sound effects.
Our view on Prey
Prey has a completely crazy plot, a carnivorous, alien that assumes human form imposes himself on a pair of lesbians, one of whom is an insane control freak with a murderous past. 
It has aliens, cannibalism, lesbian sex. British exploitaition st its best. Exploitflix thumbs up!
