Of Unknown Origin (1983)

R  |   |  Horror  |  24 November 1983 (USA)
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Ratings: 6.2/10 from 1,643 users  
Reviews: 34 user | 38 critic

A man who recently completed rebuilding a townhouse becomes obsessed with a rat infestation until it becomes an interspecies duel.



(novel), (screenplay)
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Cast overview, first billed only:
Bart Hughes
Lorrie Wells
Eliot Riverton
Louis Del Grande ...
Meg Hughes
Keith Knight ...
Hardware Salesman
Dan Errol
Peter Hughes
Jimmy Tapp ...
Meg's Father
Gayle Garfinkle ...
Janis Wycoff
Earl Pennington ...
Mr. Thompson
Jacklin Webb ...
Newspaper Vendor
Bronwen Mantel ...
Florence Riverton
Monik Nantel ...


Bart Hughes has a pretty good life, a beautiful wife, a young son, a good job with promotion prospects, and a renovated brownstone in New York. When wife and kid leave for a vacation, Bart stays behind to work on a project that will earn him that promotion, unaware that a certain inhabitant of his basement has other plans for his time. Bart goes a bit bonkers trying to kill this rat, destroying most of his house in the process. Certain allegorical elements tie the household conflict to the "rat race" in his office, but the main event is certainly the night-and-day contest of wills between man and rodent. Written by Chris Holland <stomptokyo@aol.com>

Plot Summary | Add Synopsis


The terrifying last word in home invasion from the director of "Tombstone" and "Cobra." See more »




R | See all certifications »

Parents Guide:






Release Date:

24 November 1983 (USA)  »

Also Known As:

Origem Desconhecida  »

Filming Locations:

Box Office


$4,000,000 (estimated)

Company Credits

Show detailed on  »

Technical Specs

Sound Mix:


Aspect Ratio:

1.85 : 1
See  »

Did You Know?


Favorite film of Stephen King. See more »


Bart Hughes: You never said anything about rubber gloves, you boneheaded fart.
See more »


Referenced in WildCat (2007) See more »

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User Reviews

I am adopting cats.....yesterday!
17 March 2009 | by (Miami Beach, Florida) – See all my reviews

I give this one a ten. How? Well, if you love rats, you will hate me. Let me just start off by saying I have never written a public comment, so do be gentle. I am also rather desensitized to horror films. Salo, Irreversible, and others I am ashamed to mention, hardly phase me. I've seen other rat films. Older rat films, and new ones haven't bothered me. I had purchased this film with about 20 others, and it looked silly, was inexpensive, so why not? I find myself awake this morning at 4:30 am, and in need of mild entertainment. Here is where my horrific morning begins.

I am a 24 year old female, so to all you guys reading this, never show a woman this movie. Show her Cannibal Holocaust, not this. I slap in my DVD of this film, pull my covers back and wait for 90 minutes to pass. 10 minutes later I am screaming like a wild woman being attacked by the Texas Chainsaw Massacre. This movie is INSANE! I own 1000 horror movies, and I thought I had built up enough tolerance and desensitization to endure any form of human torture. Wrong! This is one evil, hideous, demon possessed rat. By the time an hour had passed I was clutching on to my baseball bat, and wouldn't you know? A shadow from my ceiling fan caused a sharp movement on the floor., and I was running down my hall in a terrified frenzy. It may be that girls like me just can't cope with a rat, but it might just be that this movie is hell bent on preying on everyone's natural dislike for these foul little beasts. I sat and hoped that WHAT I KNEW WOULD HAPPEN…would not. It did. I was so happy when this movie was over, but ever happier I gave it a chance. It is rare I feel fear, and this was a great reminder. It isn't Citizen Kane, sure, but it is more entertaining. It is my worst fear, realized. Except for that whole broom in girlie prison thing. I digress.

I know you guys are tough! I know you ARE THE MAN! BUT! If you can make it through this movie without jumping in your seat, well, you should join the Navy Seals. Or better yet….you would make a great executioner. This is a nerve wrecking modern spin on MAN VS. MONSTER. No kidding!

This movie gets a ten from me. After sitting through 1000 movies that people say are scary, I find this fabulous little gem, and come to realize just why I love horror. This is horror. Nobody gets tortured, raped, or beheaded. That is fine, considering how brilliantly the film makers took a simple fear and found a way to torture the audience, and not one lesbian bimbo vampire was skinned alive. I was impressed.

I wish I was so well versed and I could give you the most complex analysis of the technical specifics. I am not. Peter did a great job in being convincing, and some of the camera work is great I think. The camera often acts as the eyes of this evil monstrosity. The mans wife in this movie is really pretty, and you see her boobs. So, you guys might like that if nothing else. I think the film was very well done, and most effective at making it's point. I would tell you all about the shocks, but that would ruin them for you. Some must be seen to be believed.

I'm a girlie girl, sure. I bet you can't make it through this movie, in the dark, without your baseball bat either. If you are on the fence and wondering if you want to give it go, do it. But, remember, it can bring out your feminine side. Isn't that the definition of scary for you boys?

Either way, for my own sanity,I am adopting a cat today.

16 of 16 people found this review helpful.  Was this review helpful to you?

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