Thief: The Dark Project

You play Garrett, a street urchin who is taken in and trained by the secretive organization of the Keepers. However, you decide to use your talents for your own ends and return to the streets to earn your living as a thief.

You must hide in shadows to avoid being seen.  Guards can also hear you as you walk, and thus care must be taken as you stalk silently toward your objectives.  The player must be cunning, and use his mind to defeat his enemies and achieve his goals.