This is the story of a man (Bart Hughes played by Peter Weller) who becomes obsessed with a little rat problem he's having at his newly renovated house. Instead of focusing on Bart's growing insanity, the director unfortunately showcases the rat as a vicious and dangerous beast. Although there are some quite effective closeups of the rat-villain, we never really feel any threat emerging from this little creature. Bart's obsession seems all but unbelievable. It's implausible that he would not just move to a hotel or try (harder) to contact an exterminator. Also, the movie just doesn't seem to have any real purpose. After a quick showdown it just ends, leaving some plot lines (Bart's job, his relationship to his family) unresolved.
"Of Unknown Origin" is still a very watchable movie. The pacing is quick and Weller does a pretty decent job in this one man-show. Had director George P. Cosmatos added anything to make it more than a mere monster movie, "Of Unknown Origin" would no be the obscure left-over from the early 80's that it is.
