In the blink of an eye, thirty thousand bewildered Japanese gamers are whisked from their everyday lives into the world of the popular MMORPG, Elder Tale, after the game's latest update—unable to log out. Among them is the socially awkward college student Shiroe, whose confusion and shock lasts only a moment as, a veteran of the game, he immediately sets out to explore the limits of his new reality.
Shiroe must learn to live in this new world, leading others and negotiating with the NPC "natives" in order to bring stability to the virtual city of Akihabara. He is joined by his unfortunate friend Naotsugu, having logged in for the first time in years only to find himself trapped, and Akatsuki, a petite but fierce assassin who labels Shiroe as her master. A tale of fantasy, adventure, and politics, Log Horizon explores the elements of gaming through the eyes of a master strategist who attempts to make the best of a puzzling situation.
Out of nowhere, Shiroe finds himself in the city of Akihabara, inside the game "Elder Tale". Thirty thousand Japanese players have been locked inside the game! The world on the other side of the screen becomes reality, and amidst the chaos Shiroe finds his old friend Naotsugu. And as they relax at finding one another, they meet the powerful assassin "Akatsuki". Akatsuki has a request to make of Shiroe...
The Apocalypse has locked thirty thousand players inside the game, and no one knows what to do. The larger guilds are taking over Akihabara, and outside the city violent groups are Party Killing other players. A young female member of Marielle's "Crescent Moon Alliance" is trapped in Susukino, far to the north, and needs their help. Shiroe feels somewhat embarrassed, but makes a decision.
Serara, a young female member of the guild "Crescent Moon Alliance", is trapped by mysterious men in the northern city of Susukino and needs help. Shiroe and his friends travel to reach her. Annoyed by the game's tasteless food, they travel northwards, and go inside "the depths of Palm", a crumbling series of old mining tunnels. There they meet creepy monsters...
Shiroe, Naotsugu, and Akatsuki reach the northern city of Susukino, and safely meet Serara. With the help of the mysterious swashbuckler Nyanta, they plot to leave Susukino. But the evil guild Brigantia wants to stop them. The high-level monk Demikas attacks them. Can they overcome the odds?
Shiroe and his group take Serara southwards. On the way, they stop at the house of one of the "People of the Land". The people of the land were originally only characters in the game, with no personalities or unique traits of their own, but as Naotsugu talks to them, something seems odd... The party gradually realizes that the world isn't the same as it was when it was a game.
Shiroe returns to Akihaba and Marielle tells him what the town is like. The initial chaos has subsided, but the larger guilds are in control, and evil guilds are tricking new players and taking advantage of them. Shiroe is angred by this, and tells Naotsugu, Akatsuki, and Nyanta of his plan. And then he tells the Crescent Moon Alliance that he's going to clean up the city of Akihabara.
Nyanta told Shiroe the secret of making real food in this world. With Marielle's help, the Crescent Moon Alliance begins a fast food stand, and their "Crescent Burger" is hugely popular with players who are sick of tasteless food. BUt Shiroe's real goal isn't to sell hamburgers, and with Henrietta he begins to work on the next phase of his plan.
After the success of their Crescent Burger, Marielle and Henrietta meet with the members of the major crafting guilds of Elder Tale: Karashin of Shopping Street 8, Michikata of the Marine Agency ,and Roderic of the Roderic Merchant Association. They use Shiroe's plan to dangle the secret recipe of the Crescent Burger in front of them, and the talented account Henrietta opens negotiations. What she wants is...
To make the city of Akihabara safe, Shiroe calls all the major guild masters to the guild building. His goal is to create a Round Table Conference, which will rule the city. But everyone there wants something different, and his plan is about to go bad. What amazing trick does Shiroe have? Meanwhile, behind the scenes of the conference, the plan to free the younger players from the evil guild Hamelin continues. The strategist SHiroe's quiet battle in Akihabara continues!
Shiroe confronts the 10 guild masters who represent Akihabara with the need to revitalize the town and bring peace and order. His calm and forceful manner brings them over, and the government of Akihabara, the "Round Table", is founded. After this work is done, his guild, "Log Horizon", joyously moves to their new location. That night, Nyanta fixes them his special curry.
The Free Cities of Eastel are the first to notice the founding of the Round Table. They send a messenger to Akihabara and invite Shiroe and Crusty to their conference. What are the nobles planning at their ice-covered palace? Meanwhile, Minori and Touya and the other new playesr are going on a camping trip at the beach to learn to fight. Marielle forgets her role as leader (?) and enjoys the salt air fun.
The young players travel the Xantleaf peninsula at the camp. Minori, Touya and Serara meet up with new players Isuzu the bard and Rundel Haus the sorcerer. They head into the "La Granda Forest" dungeon, where skeletons await them. The easily-spooked Serara, the strong-willed Touya, and the proud Rundel Haus... will the five of them be able to work together in their first party fight?
Shiroe, Crusty, and Michitaka are invited to the palace by the Free Cities of Eastel. The nobles of the land invite the three of them to various meetings and seem to be trying to find out more about Akihabara and the Round Table. Crusty is attracted to the daughter of Duke Cowen, who is noble, beautiful, but seems somehow lazy...
Shiroe and Akatsuki are invited to the room of the mysterious mage Reagan. Shiroe is shocked at the revelations he offers about the world of Elder Tale.
Touya and Minori and the rest of the players in the training camp are hitting a wall with the way they fight. And Minori's suggestion is that they introduce themselves to one another!
Just as the Sahaugin attack begins on the Zantleaf peninsula, the goblins are seen advancing further inland. Will they attack Laynessia's homeland, Maihama, or Akihabari?
The lords of the Free Cities of Eastal begin an emergency conference to discuss the goblin invasion. The protectors of the land people, the Izumo Knights, are missing, and they'll have to depend on the adventurers.
Princess Laynessia Cowen vows to go to the city of Akihabara herself and beg the adventurers for help against the goblins. The members of the Crescent Moon Alliance can't conceal their excitement at meeting a real princess.
Zantleaf is attacked by monsters from both the land and the sea, as the adventurers continue to defend it. Inland, Crusty's army launches a raid on the goblin's main force. At the town of Choushi by the sea, the new players are fighting too.
Rundelhaus hid from his friends that he was one of the land people, but the price of fighting off the dire wolves was that he took a fatal wound. If they can't save him, he'll die and he won't revive.
A victory party is held at the palace of Eternal Ice to celebrate the adventurer's defeat over the monsters. Crusty takes the princess's hand and leads her in a dance signifying the reconciliation between the adventurers and land people.
Fall has come to Akihabara. After defeating the monsters, Shiroe is fighting a losing battle against paperwork, but the town is filled with cheer as the first event the Adventurers have ever had, the "Scales Festival", is approaching.
The second day of the Scales Festival in Akihabara arrives. Akatsuki has gotten closer to Shiroe, and so is very happy all day, and even seems to be enjoying her fights with Naotsugu. Meanwhile, Minori is uncertain with how to deal with her feelings towards him, and goes to speed to Karashin. Karashin is overloaded with paperwork so she decides to help. It seems like a lot of land people merchants have come to Akihabara...
Akihabara is amazingly busy since the Scales Festival began. There are many land people in town, causing accidents, spreading rumors, and starting couples' fights, and even Shiroe can't deal with them. An influential noble named Marves arrives from Minami to see Laynessia. Laynessia tries her best to deal with him, but he gets closer and closer to her...
Marielle and Henrietta put on a fashion show as the town reels from the Minami decoy operation. Akatsuki walks down the runway in her colorful clothes, but Shiroe is nowhere to be seen. That night, Shiroe is met by a beautiful and enchanting "queen of darkness." Shiroe is tempted he reaches the heart of the conspiracy...