After a long and difficult chain of events connected to the Xenos, Bell Cranell finally becomes firmly the focus of attention of everyone living in the labyrinth city of Orario. But everything has its price. Of course, it’s pleasant to bask in the glory and enjoy an increased level of authority, but new rights also bring new responsibilities. Bell and his companions receive an official assignment from the guild to carry out their first full-fledged “Expedition” deep into the Dungeon. And when the adventurers take their first steps onto new floors—no matter how prepared you are— the ruthless labyrinth catacombs always find a way to test uninvited guests to the limit of their abilities…