The trophy room scenes were much longer in the preview version of 78 minutes: there were more heads in jars. But there was also an emaciated sailor, stuffed and mounted next to a tree where he was impaled by Zaroff's arrow, and another full-body figure stuffed, with the bodies of two of the hunting dogs mounted in a death grip. Preview audiences cringed and shuddered at the head in the bottle and the mounted heads, but when they saw the mounted figures and heard Zaroff's dialog describing in detail how each man had died, they began heading for the exit - so these shots disappeared.
The actor playing "Ivan the Cossack" was Noble Johnson, a multi-talented African-American who was a childhood friend of Lon Chaney. This is the earliest known instance of a black actor working in "whiteface" to play a Caucasian character.
Most of the standing sets from King Kong (1933) were used in the making of this film, including the gate (which was eventually burned down in the "Burning of Atlanta" sequence of Gone with the Wind (1939)). This film and "King Kong" were shot at the same time, though "Kong" was released later (probably due to the special effects required for it).
The failure of the original copyright holder to renew the film's copyright resulted in it falling into public domain, meaning that virtually anyone could duplicate and sell a VHS/DVD copy of the film. Therefore, many of the versions of this film available on the market are either severely (and usually badly) edited and/or of extremely poor quality, having been duplicated from second- or third-generation (or more) copies of the film.
Zaroff's dogs were Great Danes borrowed from Harold Lloyd. While big, Great Danes are not especially threatening, so with their coats subsequently darkened and they were filmed at an especially low angle to appear more menacing.
During WWI, Leslie Banks suffered a disfiguring injury that paralyzed the left side of his face. Never once letting this injury interrupt his career, he went back to the stage after his release from service in 1918, and within six years was an international stage star. He was one of the most popular British actors on Broadway throughout most of the 1920s since his appearance in the 1924 production of "Peter Pan" as Captain Hook.
This film was released before the Hays Code was widely enforced. As a result both Joel McCrea and Fay Wray were able to get away with wearing relatively little clothing in comparison to other films of the era. Within a few years, however, the film was considered indecent and too revealing. It was barred from re-release and was not shown publicly for several decades.
The drunken Armstrong is a loaded script element: he's supposed to be annoying. At the time this film was released, Prohibition was still in effect, but the law was widely ignored. Producer Merian C. Cooper was strongly critical of alcohol use and of the glamorization of drunkenness in movies. There is a similar scene in both Mighty Joe Young (1949) (where inebriated nightclub patrons precipitate the creature's escape and rampage) and The Son of Kong (1933) (where drunkenness proves disastrous for the heroine's father). Zaroff's reveling in his hunting exploits was also deliberate beyond the needs of the story, downplaying its glamorization in other movies of the period.