Miklós Rózsa score for this film was composed in the style of Bernard Herrmann who worked regularly with thriller director Alfred Hitchcock. This film's composer Rózsa had worked with Hitchcock himself once, on Spellbound (1945).
The film was made and released about two years after its source novel "The 13th Man" by Murray Teigh Bloom had been first published in 1977.
After appearing in this 1979 Hitchcockian homage, Roy Scheider would appear in another, Still of the Night (1982), just a few years later in 1982.
The movie's MacGuffin was a mysterious anonymous letter written in Hebrew and known as a "goel hadam" note. "Goel Hadam" is a Hebrew/Jewish phrase which translates into the English language as an "Avenger of Blood".