Goblins are the weakest of the monsters, with only a numerical advantage on their side. No warrior would ever dedicate his life to eradicating them...except Goblin Slayer.

As his reputation spread, he received a quest from none other than the Archbishop of the Supreme God - Sword Maiden, an adventurer Gold rank, famous for destroying the Demon Lord. The former heroine brings a report of goblins hiding beneath the prosperous and peaceful water city, and asks Goblin Slayer and his companions to investigate this place, since there are no more willing ones. Searching the catacombs beneath the city, the group discovers that the problems run much deeper than any of them thought. How do all these goblins get into town? And why is the Sword Maiden so desperate?..