Their upcoming stealth-action title, Dishonored, looks pretty darn interesting:

And who doesn’t love a neo-Victorian motif?

GameInformer has some excellent coverage of the game, which gives a few details about what Arkane is trying to accomplish therewith:

Why should you care?
Even if you haven’t played them, you’ve undoubtedly heard of Thief and Deus Ex. One of the main minds behind those two games, Harvey Smith, is the co-creative director of Dishonored along with Raf Colantonio, the founder of developer Arkane Studios. The two share a vision of a game that gives players the power to be creative with their skills and tactics, and invites them to come up with interesting solutions to the obstacles in front of them. Arkane is known for its immersive first-person gaming (Arx Fatalis, Dark Messiah of Might & Magic), and the power of a talent-driven publisher in Bethesda (The Elder Scrolls IV: Oblivion, Fallout 3) behind the team is promising.

How are they going to do that?
Dishonored has several major elements that combine to create its unique gameplay: mobility, powers & gadgets, environment, and AI. The trick is that a single power doesn’t just do damage or heal you. You can combine them organically to create interesting effects. Stop time and knock a bunch of stuff off a table in one direction then book it in another, so the guards search for you in the wrong place. Summon a swarm of rats to attack one guard, but possess one of the rats and escape in the chaos. Every problem has as many solutions as you want it to.

What’s the catch?
It’s an assassination game that reacts to how violent you are. An unusual “chaos” system tracks how much collateral damage you cause, and the game world changes as a result of your actions. Unlike a light/dark side meter, though, it’s a behind-the-scenes element that affects story decisions without punishing the player or pushing them to play one way or another.

Interested yet? The game comes out on PC and consoles later this year; watch for it.