"Could it be - Satan!"

FRANK: “Hey, when the devil shows up, you think he’s gonna have little red horns and carry a pitchfork? No, he’s gonna work for Amnesty international, and he’s gonna give all of his money to the homeless.”
DR. PINCUS: “Well, if he did all that, wouldn’t he lose the title ‘the devil’?”
Hmmm. . .I think he would still be the devil. Of course, Dr. Pincus's answer is revealing. It reflects the world's minimalist view of goodness - a standard far below holiness. If he is a "good person," he CAN be the devil.