Reading the interview, looking at the screens and the flash movie this may finally be a cool first person shooter.
Painkiller is the nickname of a mercenary who kills the undead for money. Evil creatures keep their nests in typically abandoned locations like caves, private castles, etc. Painkiller "cleans out" these places for a living. In one critical mission, he realizes he's been thrown into a situation that's more serious than a bunch of zombies hiding in a forgotten place. He doesn't like the idea of being someone's toy, so he decides to play his own cards. That's the setup for the story. It's a roller coaster ride from here on out.
News source: House 'O Spank
View: Painkiller webpage