Trivia

Debut cinema movie of actress Shannon Tweed.

First lead-starring role in a film or television production of actor Peter Weller.

Of Unknown Origin (1983) was made and released about two years after its source novel "The Visitor" by Chauncey G. Parker III had been first published in 1981.

John Waters has called this film the "greatest rat movie."

Of Unknown Origin (1983) won two awards at the Paris Film Festival in 1983. They were the Best Actor award for Peter Weller and the prestigious Grand Prix award for the film's director George P. Cosmatos.