Hi everyone, first post after many years of lurking.
First of all, excuse me if my english is improper from time to time, since it isn't my first language.
I am writing down a new campaign where there is basically two villains. The first one being the evil bodyguard with his own intentions and the "mastermind" ala Star Wars. I came down with the idea that my "vader" would be a black knight with incredible charisma and good social skills and the Princess of the capital(who is an orphan and will soon come to adulthood and therefore would have access to the throne)has basically a huge crush on him.
But here comes the twist: The players will come to know rapidly who the black knight is, without actually being able to destroy him because of his position has the princess crush and because there is no evidence that he is the bad guy. He IS obviously the bad guy in the player's eyes(and in fact, he also is the bad guy in reality) but everyone else sees him as a charming, handsome knight. So the word of the players is worthless and the villain can keep trying to bring them down while they try to ruin his plans.
Now my concerns are simple: Is it realistically feasible? and what should I avoid to make the game fun to everyone, as I don't want to frustrate my players with the privileged position of the black knight. To conclude, he is definitely not invincible or has godly powers, he is just a strong paladin with good social backup plus protection from his "master", a Dark cleric who tries to find the secret to eternal life. The black knight follows him because he wants eternal youth(and more importantly, beauty).