In a video diary posted on CVG (along with a few new screens), Arkane co-creative director Raphael Colantonio introduced the setting behind Dishonored -- a "retro-futuristic" world based on London of 1666. And as such, all the futuristic and offensive technology found in the game world is powered by ... whale oil. On top of that, you have "spells" and abilities that allow you to possess people and animals and warp from place to place.
Colantonio outlined an emergent gameplay mechanic discovered by testers, in which the player uses a "stop time" spell right when an enemy fires, then possesses that enemy, and walks him in front of his own bullet before exiting the body and restarting time. We think we saw something like that on an episode of Out of this World.