Thanks to Souma Yukihira, Erina Nakiri, and the rebel forces overthrowing the regime of Azami Nakiri—the previous school director—and the former Elite Ten, Tootsuki Culinary Academy is back in order. However, its students have one more great battle ahead of them: the BLUE, a competition where young chefs seeking world-class fame compete. Faced with new trials and rivals, Souma and his friends will fight to conquer the BLUE and to defeat Asahi Saiba, the leader of an underworld organization of chefs known as Noir, who once defeated Souma and his father in a Shokugeki.

E-Rantel, the capital city of the newly established Sorcerer Kingdom, suffers from a dire shortage of goods. Once a prosperous city known for its trade, it now faces a crisis due to its caution—or even fear—of its king, Ainz Ooal Gown. To make amends, Ainz sends Albedo to the city as a diplomatic envoy. Meanwhile, the cardinals of the Slane Theocracy discuss how to retaliate against Ainz after his attack crippled the Re-Estize Kingdom's army, plotting for the Baharuth Empire to take over the Sorcerer Kingdom. However, when Emperor Jircniv Rune Farlord El Nix arranges a meeting with the Theocracy's messengers at a colosseum, he is confronted by none other than Ainz himself. With their secret gathering now out in the open, the emperor and his guests learn that Ainz has challenged the Warrior King, the empire's greatest fighter, to a duel. With Ainz's motivations beyond his comprehension, Jircniv can do nothing but watch as humanity's future changes before his very eyes.

While exploring Wiz's magic shop with his party, Kazuma Satou finds a magical wish-granting choker and decides to try it on. Only then does Wiz tell him that the choker strangles its wearer to death in four days unless their desires are fulfilled. This wouldn't be a problem if Kazuma knew what his wish was. Fearing for Kazuma's life, Aqua, Megumin, and Lalatina Ford Darkness Dustiness all agree to do his bidding in order to satisfy his desires and hopefully grant his wish, no matter what he asks for.

After bonding over a tragic loss, the long-suffering Nanachi joins Riko and Reg on their journey into the depths of the Abyss. Awaiting the children is the Sea of Corpses—the Abyss's fifth layer, and the deepest level from which a traveler can return without losing their human form. The masked sadist Bondrewd stands between the children and the rest of their adventure. Bondrewd's horrific laboratory serves as a final checkpoint for those wishing to traverse deeper into the Abyss, and the sociopathic scientist has no desire to allow Riko's party to pass through at no cost. Deeply scarred by Bondrewd's impact on their childhood, Nanachi is engulfed in turmoil over his resurgence in their life. Bondrewd's only apparent weakness is Prushka, a brash child who claims to be his daughter. Riko, Reg, and Nanachi befriend Prushka and work with the girl to overcome her father's machinations and breach the Abyss's sixth layer.