We have this instinctive habit of placing villains in abstract categories that sufficiently correspond to their moral wickedness. The greater the enormity of their sin, the faster their entry into categories of depravity. We adhere to this rule of thumb with such rigidity that we don’t ever stop to think about the changes this or that stock bad guy might have undergone. Just a whiff of their motivation, and we as readers/viewers seem to lay out for them the moral path to be walked, and behavioral patterns to be followed. Thus the depraved soul should not be allowed to move us with his refined hilarity. The evil Megalomaniac should be the last person to make you rethink your worldview. We have got it all sussed out in our mind.
Any departure from this ideal of depravity will shatter our most conventional perception of what constitutes evil. Glimpses of logical clarity in someone like joker will appear to you not only ludicrous but unethical. You find Hannibal lecter’s refined tastes to be in jarring conflict with his cannibalistic instincts. The point of these characters is not to generate empathy through some kind of perverse sophistry, but to send us into a momentary daze of moral confusion. So later when you shake off the daze, you feel like a better person, and joker a better villain.
In the photo: Joker, Hannibal Lectre, Nosferatu