The premise of this film isn't exactly original, but a story like this has great potential both for a psychological thriller and for a fun horror flick...but unfortunately, Or Unknown Origin doesn't quite manage to excel at being either. The focus is more on the battle between man and rat than providing the sort of schlocky horror that the eighties produced so prolifically, which is fine; but it never probes too deep into the psyche of the central character, and the film plays out like a movie that should be fun, but largely isn't. That's not to say that it's a bad film, however, as there are a lot of good ideas on display, and the film also features what may be a career best performance from Peter Weller. The plot sees a man who recently completed the rebuilding of a house being left alone when his wife and child go on holiday. He stays behind to try and win a promotion, but he doesn't count on an onslaught of torture when it turns out that the house he put together has become infested by a rat. What follows is an all out war between man and one of the world's most notorious pests.<br /><br />Rats are one of horror cinema's most popular animals, and it's not hard to see why. There is a scene in this film that sees the central character make a case against rats, and it really makes you realise the reason why these animals are so often feared. Of Unknown Origin starts out slowly, but builds some momentum half way through when our hero begins his personal war against nature. I wasn't expecting much after the first half hour, but the film surprised me somewhat by the way it eventually comes together, climaxing with an exciting sequence that sees the central character really go off the rails. Peter Weller really is superb in the lead role, and I wouldn't be surprised if this film was the reason he went on to take the lead role in the classic Sci-Fi thriller 'Robocop'. It's a shame that director George P. Cosmatos doesn't seem too keen to get fully inside the character's head, as the potential for a great psychological thriller is definitely there. This film may have been better if it was handled by someone like David Lynch, but despite its imperfections; Of Unknown Origin is still worth seeing.