The character Boris Mitrov is loosely based on Boris Morros, who was identified by the U.S. government as a counterspy in 1957. Extensive details on his life and career can be found in the entry on this film in the American Film Institute on-line Catalog.
The off-screen film narration belongs to well-known newsman Clete Roberts. Onscreen credits list Pierre Poincarde as director of photography, Moscow, Russia.
The surnames of producers Louis De Rochemont and Louis De Rochemont III are misspelled as Rochmont in the onscreen credits.
Ted Knight, who played Prof. Vasheen, would also guest star on Ernest Borgnine's series McHale's Navy (1962) as a general.