aka Project Genocide, aka Alien Encounter, aka War of the Aliens
How bad is it? Silly campy nonsense.
Should you see it? Sure.
The stories behind this film are better than the film itself: Christopher Lee and Robert Vaughn both claim that they were duped into making this, being told it would be a serious "Star Wars"-type film, rather than the camp it is; the Canadian film (the first SF film from Canada since... well, ever) may have been made as a tax shelter or it may have been hastily assembled to beat "Close Encounters" to the screen and it may have been either a serious homage to 1930's serials and 1950's sci-fi or it may have just failed. Beside Helen Shaver, there are no other names in the cast. Aliens decide to colonize Earth and use a suicide ray, leading to fun scenes of people strangling themselves; they also take a sperm sample from an Elmer Fudd wannabee. There's bizarre - and in one case rather sexy - costumes, robots that look like they found the top of "Robot Monster," special effects that range from excellent to "my Gawd that's lame," aliens that are telepathic just to cut down on dialogue and more references to the Bermuda Triangle and pyramids than in "Chariots of the Gods" (which clearly inspired the makers). It's slapdash, it's puerile, it's worth checking out.