I rented this 1947 film-noir from Netflix upon learning it puts a spin on this word "geek."
Having just plunked down my credit card to gain access to O'Reilly's Safari, tempted inside by virtual books on Python's TurboGears & SQLAlchemy, and having just registered as a speaker at O'Reilly's OSCON this summer, I'd say "geek" pretty well describes my ethnicity, after sixty years of further spinning.
Knowing the movie was based on a novel, I was a little apprehensive that this perhaps obscure geek reference wouldn't have actually made it from the book to the movie. I needn't have worried. Right from the opening scene, that word defines the entire arc of the story.
Skillful carnival mentalists, in some respects forebearers of modern psychologists (as the film cleverly suggests), may feel tempted to cross the line between giving 'em their money's worth (hard work, like acting) and simply duping those with real money to lose.
Psychological manipulation, for those with the knack, becomes a hustle, and given the associations of so-called mentalism, going back to ancient Egypt and before, the big time version of this hustle, the so-called "spook business" in this movie, involves recruiting new true believers, especially among skeptics with bucks -- another way of taking cruel and cynical advantage of people's deepest vulnerabilities.
However, psychological forces are real, and tricksters weaving complicated webs based on lies mixed with secrets, have a way of going off the deep end long before their intended marks suffer the fully intended consequences of their deviousness.
The geek in this movie represents the abject fate of a dirty trickster turned monster, now so desperate he'll bite the heads off live chickens just to stay in the game (back to hard work again). His life has become a form of punishment, proving that it's not smart to screw with people's minds for ill-gotten gains. So yes, the film has a moral message, even for geeks of today: if you have circus level skills, use them wisely. Honest work will get you further in the long run.
Ironically and somewhat paradoxically, ethnicities wherein communicating with the dead might be considered routine would appear less amenable to such ruses than the high society types depicted here, so desperate to believe and projecting occult powers onto others in order to compensate for their own sense of ignorance and doubt.
This design pattern of an authoritative elite, priest-like in its powers, vis-a-vis some exploitable army of "chumps," is what makes these abusive indulgences more likely to occur. Stronger philosophy for children programs in the schools might help inoculate future generations against becoming easy prey for cultists, charlatans, snake oil salesmen of all description.