On the night his favorite MMORPG is scheduled to be shut down, veteran player Momonga stays logged in until the clock hits zero. The screen goes dark for only a few moments before he finds himself completely immersed in the online world of Yggdrasil. Left with all of his character's devastating powers, total dominion over his loyal NPCs, and nothing better to do...Momonga decides to try his hand at taking over the world.
All the hours he's spent grinding and dungeon crawling have certainly paid off, and as he tests his strength on local rogues and legendary beasts he comes to realize that not one opponent can stand against his might. Embracing his new identity as the fearsome mage Ainz Ooal Gown, Momonga continues his search for bigger, badder adversaries. Leaving the people of Yggdrasil to wonder-who exactly is trapped with who?