The whole story is about an ancient book in which is written how to release the deamon of underground. As it would've been really dangerous weapon if the book had got in wrong hands, it had been protected by the order of light (Lux Veritatis... Does it remind you of something?) It was in safe for whole centuries. But what if there's a trator within the order? Then he has to be stopped, right? And if so, what will you do if the trator is someone you love someone who's really important for you?
What will you do then? Will you stay on the side of light? Or will you help him although it may cause an apocalypse?
This is the first decision one of our heroes has to make in our story.