First announced to the trades as a production in progress on October 16, 1982, the film is based on a paperback novel by Chauncey G. Parker III whose rights were snapped up in February of 1981 by Canadian company Filmplan International via producers Pierre David, Victor Solnicki, and Claude Héroux. Those names should sound familiar to any '80s sci-fi or horror fan as they were three of the biggest movers and shakers from the Canadian tax shelter era and its immediate aftermath that resulted in a barrage of notable genre films like The Brood (1979), Scanners (1981), and Visiting Hours (1982). Ultimately Solnicki departed by the time the film went before the cameras, with Héroux serving as producer and Pierre David as executive producer.
One fan of the source novel was director George P. Cosmatos, an Italian-born filmmaker who studied under Otto Preminger and made a name for himself with ambitious "Euro pudding" productions like Massacre in Rome (1973), The Cassandra Crossing (1976), and Escape to Athena (1979). The move to North America with this film would be fortuitous as his ability to work efficiently and on time led to a pair of Sylvester Stallone vehicles, the spectacularly successful Rambo: First Blood Part II (1985) and the hyperbolic cult favorite, Cobra (1986). Cosmatos took the initiative with this project when he tracked down the Canadian rights holders and offered his services, which were quickly accepted. "We've tried to create terror where terror belongs," Cosmatos noted in the film's press materials, "but without those torrents of blood on the screen. Instead of that you imply, you keep twisting and turning the mind."
Principal photography began in December of 1982 in Montreal as a co-production with Warner Bros, who has held rights to the film in the United States ever since. Cast in the lead role as embattled Bart Hughes is Peter Weller, an up-and-coming actor who made his Broadway debut in Sticks and Bones (which he also took to London) with additional theater roles in Summer Brave, The Wool Gatherers, and Full Circle. Weller made his feature debut in Butch & Sundance: The Early Days (1979) and quickly moved on to roles in Shoot the Moon (1982) and Just Tell Me What You Want (1980). His performance here demonstrated his ability to carry a film as the leading man, which was enough to earn him the title role in the financially unsuccessful but now hugely popular The Adventures of Buckaroo Banzai Across the 8th Dimension (1984) as well as his most famous role to date, officer Alex Murphy, better known as RoboCop (1987). He and Cosmatos would also team up for another horror film with a more nautical and action-oriented twist, Leviathan (1989).
Presumably because it didn't fall into the then-popular slasher wave of the early '80s and had enough professional gloss to pass as a mainstream thriller, Warner Bros. did its best to camouflage the subject matter of Of Unknown Origin and never used the word "rat" in any of its promotional material. Initially billed as a "suspense drama" and then in the press kit classified quite amusingly as "a suspense thriller that charts the course of one man's victory over obsession," it was also described as "a kind of allegory of the 1980s - about our elegant goals and our primeval rage to survive." Much more direct was The Hollywood Reporter, who counted themselves among the film's several critical admirers: "Those who have a hankering for a good rat film will find one in Of Unknown Origin... This presentation is a sharp psychological horror story whose antagonist just happens to be a large, fang-toothed rodent." How could anyone resist that?
By Nathaniel Thompson
