I like the movie, for what it is. I would like to see the earlier version, and compare. I've always thought of Warner Oland as kind of a ham. But it's impossible to judge by 1931 standards in 2007, so what do I know? The Karlov question had me curious. This is what Wikipedia had to say (yeah, I know-- it's Wikipedia, so who knows if it's true?):
"In 1922 the book was made into a Broadway play and the following year a motion picture. A second film version appeared in 1931. It is said that a young Boris Karloff, who previously had a few uncredited film roles, chose his stage name for his first screen credit in 1920 from a Russian mad scientist character named "Boris Karlov" in this novel. The name 'Boris Karlov' was used from MacGrath's book for the 1922 Broadway play, but by 1923 with actor Boris Karloff using the similar sounding variation, the film version renamed the character, played by Wallace Beery, 'Gregor Karlov'. In the 1931 film version, however, with Warner Oland playing the character, the mad scientist's name is restored to 'Boris Karlov', less than a year before Frankenstein would make Boris Karloff a household word for generations. Ironically, Boris Karloff would play many mad scientists on screen, but never 'Boris Karlov'."
As a side note for those interested in original sources, the Harold MacGrath novel "Drums of Jeopardy" is available as a free e-text download at Project Gutenberg.