Released between George Luca' "Star Wars" and Steven Spielberg's upcoming UFO thriller "Close Encounters of the Third Kind," the low budget, low-caliber Canadian sci-fi melodrama "Starship Invasions," now at area theaters, may be strategically placed to pick it up some loose change at the box-office. However, it had better pick it up and tiptoe out of town before too many patrons have a chance to retrace their steps and began blowing the whistle.

The film was shot last year in and around Toronto on what looks like a junior prom budget. The original title, "Alien Encounter," anticipated the Spielberg movie, while the new one obviously recalls the Lucas movie, and Warner Bros., the American distributor, has tried to make this feeble acquisition look stronger than it is by preparing an astute, misleading trailer which incorporates just about every active moment from the entire picture. If the movie has any high-lights, the trailer exhausts them.

"Starship Invasions" might be tolerated as an endearing clunker if director Ed Hunt were'nt so inclined to drag his feet and thereby expose his lack of resources and ingenuity to lingering ridicule. Some aspects of the presentation are amusingly reminiscent of the Z-grade sci-fi programmers of the '50s. "Invasions" is foolish or improverished enough to reply on the same murky, cheapskake color processing, the ragged plotting, the stumblebum pace, the excruiating dialogue and laughable costuming, decor, props and special effects that kept its predecessors in their obscure, derelict places.

Christopher Lee commands a band of renegade aliens who plan to resettle Earth after eliminating the present inhabitants by provoking waves of murder and suicide. In an effort to thwart his scheme the peaceable aliens, dominated by actors outfitted with huge, golobular domes and teensy ears, call upon the services of Robert Vaughn, an astronomer specializing in the investigation of UFOs. Why they need him remains a mystery, although Hunt takes advantage of his absence and the aliens' plodding preparations for an outer space shootout to tease the audience sadistically with the hint that Vaughn's wife or child could be the next suicide victims.

Hunt creates a lot of expository misery for himself and boredom for the audience by deciding that his extra-terrestrials must communicate telepathically. What this means in practical terms is that we're condemned to watch actors stare at the camera while listening to them recite sepuichral , voice-over lines on the sound-track. The actors may betray a twitch in the hollows of their cheeks and the actresses a sensual pour, but who can tell if these movements can be reguarded as expressive or involuntary?

Of course, there may be greater hazards to speaking the dialogue alound in such a movie. I was especially tickled bynthe mother required to scream, "Put that down! You'll just get them mad at us." as her kid snaps a Polaroid of a hovering flying saucer. During a domestic break Vaughn's wife pleads, "I'm interested in UFOs too, but we've got to get some time to ourselves." A robot in a funny costume topped by a helmet that resembles a bomb casing with spikes, asks Christopher Lee, "Would you like to visit our recreation room?" Lee is ushered into a lounge full of space hookers, whose scanty panties are cut within an eyelash of an "R" rating in front and leave a considerable stretch of buttocks hanging out in the back.

It takes Hunt forever to line up his wrobbly, herky-jerky flying saucers for the climactic battle, which is severely compromised by a little detail immediately called to my attention by my 6-year-old daughter: There's no way of telling the good alien' flying saucers from the bad aliens flying saucers.

Currently a "Star Wars" freak, she expressed an opinion which may be fairly typical of the audience "Invasions" would need to please: "'Star Wars' is 9 trillion per cent better." That may be giving "Invasions" the benefit of the doubr by a trillion or two.