Hidden Evil

Some things are Obviously Evil. This index is for those things that aren't. Be they cute, innocent-looking animals, small children, or just have good publicity, evil in the world often hides under an array of disguises and facades. This is a list of these various nondescript places where evil beings often lurk. These tropes are the opposite of Index with a Heart of Gold and Quirky Good.

Closely related to Evil All Along and Subverted Innocence.
http://tvtropes.org/pmwiki/pmwiki.php/Main/HiddenEvil