Introduction to Avernum III
The surface world is ruled by the Empire, and has been as long as anyone can remember. As long as you followed the rules and kept quiet, it was a good life. But stand out, not fit in, say the wrong thing, and the punishment was swift, sure, and horrible. You were cast into Exile, a huge series of caverns far below the surface of the surface of the earth, there to live out the rest of your days in misery.
But all that ended. An Exile, helped by wizardry, assassinated the ruler of the Empire. The Empire invaded Exile, and was narrowly defeated. And then nothing was heard of the Empire for years.
Now, the Exiles chafe at their imprisonment, and have found a way to reach the surface. But before they can emerge, they need to send a small group up to see who is up there, and if it's safe to come out. Your group is who they're sending up.
But all will not be as it seems, and the unthinkable has a nasty habit of coming to be. Enemies will become friends, friends enemies, and unless you test all of your skills and all of your courage, and complete an adventure taking you from one end of the continent to the other, and beyond, Exile will indeed finally be granted ownership of the surface of the world.
But that will only be because no sane person would want it.