What is the main conflict in Stone of Tears by Terry Goodkind?

Stone of Tears, by Terry Goodkind, follows a group of characters as each do their part to stop the Keeper, the ruler of the underworld, from escaping into the world of the living. Richard Rahl is a wizard that the prophecies have told about for thousands of years. Richard alone has the power to fix the veil that has been torn and stop the Keeper from destroying all life on earth.