A Hefty Mask of Evil is a Scorned Visage of Righteousness
The adoption of a caricaturistic visage that's usually employed to mock righteousness is a highly prized and wicked facade that's used to mask an evil organization or person.
Saying that someone is known for being solicitous with stuffy rightness and that someone is know as a do-gooder, it gives off the impression that they are probably imminently trustworthy in important matters. So, if a ridiculously wicked organization uses such a face, look out!