First the plot: A policeman investigates a mysterious set of serial killings in which the bodies are attacked, moved a considerable distance and systematically dissected in less than a minute. His attention is caught by an attractive blonde (Maryam d'Abo) who turns up at various murder scenes. Things get weird when he attempts to question her, for she runs, and when he pursues her, she is remarkably athletic, and, she shoots at him with a ray gun.
It turns out that the killer is a shape shifting alien criminal with psychic powers, and that she (the blonde) is sole survivor (the medical officer) of the prison ship from which it has escaped, and which is now crippled and in orbit around the Earth. She has come hunting it because it will wipe out the human race.
This has every cliché ever to appear in any science fiction movie: glimpses of a scaly monster lurking in the dark, ray guns, space ships, zombies and gob-smacked humans standing comically in front of alien shuttles going "I don't believe it". Furthermore, it is guilty of that old filmmakers' favourite, the vacuum of space which transmits sound and in which fires burn freely. This is really B grade stuff. But I think it is a good movie. So why do I like it so much?
I like it principally because of Ta'ra (d'Abo's character). This is partly because Maryam d'Abo is absolutely gorgeous, complete with her catsuit and beautiful voice, but more to the point because of the depth of the role she is given and the skill with which she pulls it off. She is alone, until she befriends the policeman, and cut off, and woefully ill-equipped to deal with her foe. Yet she approaches it with good humour, pulling the leg of the incredulous detective (once she has proved her bona-fides) about her alien abilities. Initially, she seems like a normal Earth person, describing the inhabitants of Earth as "a human race". However, gradually, differences emerge. It is these things, and the way they are treated, which give the characters depth.
For example, at one point he discovers she has one particularly extraordinary ability. When she realizes he doesn't share this gift, her response is "And you say I'M not normal!" It hadn't occurred to her that he couldn't do it. These differences cause occasional surprise, humour and, sometimes, exasperation. But she learns to use them to advantage, and when she couples them with her feminine wiles, with a wink and a nod, she can be quite effective.
She doesn't go through the movie as the standard smart-mouthed, sassy, kick-but uber space trooper, blowing everything away and taking no lip, which is what could have ruined this movie. Instead she uses her brains (including her knowledge of bio-science), good humour and charm, and barely resorts to firepower and then only as a last resort. (Her policeman friend does most of the blowing away.) The dialogue works well, and is often original (refer to Ta'ra's opinions on space ship self-destruct systems).
These qualities give the characters depth and, thus, add to the realism and tension.
And the special effects are reasonably good, with the exception of the usual nonsense about what happens in vacuums.
So I give the movie an 8 out of 10.
The subsequent television series wasn't as good. It becomes something of a standard cop programme, with ray guns. And Ta'ra's character hasn't the depth. For example, suddenly she develops an ability to develop super-weapons. Where did that come from in our ship's medical officer? If you were stranded on another planet, how many advanced weapons do you think you could build? I don't think so!
Review by astaffor from the Internet Movie Database.