You're a poor kid that lives with your sister. Crazy rich dude finds you and invites you to his castle. Once there he ends up killing your sister (so much for trusting strangers) and tries to kill you (because you both have a hero or champions blood or are part of some hero ancestry) and ends up shooting you out of a castle window where you end up laying half dead on the streets and a dog finds you. You spend the rest of the game shooting, slashing, using magic, collecting orbs, seeing people on your friends list run by you in orb form, being good or bad, and you end up killing the guy.
I can't wait for this and since my 360 just died I'm really happy Lionhead decided to go the PC route again.