Seeking to reunite the scattered inhabitants of Lurolona Village who were sold into slavery, the Shield Hero and his party head to Zeltoble to secretly compete in the underground fights at the coliseum.

Naofumi's party enters the underground arena while concealing their identity. As they win and rise through the ranks, they're forced to confront the greed and lawlessness that lurks both without and within the arena. And when the final battle arrives, Raphtalia recognizes her opponent…

Naofumi visits the slave market, where the demi-human slave Fohl asks him to save his sick sister. Naofumi asks him if he's prepared to pay the price, but… Meanwhile, Lurolona Village is beginning to come back to life as the rescued demi-humans return, but a grave danger awaits it.

The Spear Hero, Motoyasu, has been sighted, and Mirelia asks Naofumi to persuade him to return. Naofumi is about to leave his lands to Eclair and go look for Motoyasu when an unexpected visitor arrives. And they also meet someone unexpected in the town where Motoyasu is staying…

Naofumi's party is attacked by a pair of mysterious and powerful men. S'yne arrives during the battle and finally attempts to explain why she wants to become one of Naofumi's followers. Meanwhile, more villagers are training in Hengen Muso.

Ren is haunted by the deaths of his party members in a failed attempt to defeat the Spirit Tortoise, and doesn't want to believe that he might be responsible for what happened. Myne seems ready to take his side and support him, but...

Naofumi assembles a party to pursue Gaelion, who has consumed the Emperor Dragon's Core. Gaelion's transformation is profoundly sickening Filo, so Naofumi must return Gaelion to normal within the next two days.

Naofumi's party regroups and plans another assault on the Emperor Dragon. While their plan of attack comes together, Wyndia explains her connection to the dragon. This causes Wyndia to remember something very significant...

Filo has recovered but needs to gain experience to replace her lost levels. S'yne returns from the underground arena bearing a tale of a suspiciously familiar new fighter who uses a bow and goes by the alias Perfect Hidden Justice.

Rishia faces Itsuki in the underground arena. As Itsuki rants and raves, it's clear that he's also come under the mental influence of Myne and unlocked a Curse series. Naofumi evacuates the children as Rishia enters her most dangerous fight yet.

Naofumi begins training in the Way of the Dragon Vein with Sadeena and Gaelion. Back at the village, the blacksmith visits, bringing new equipment for Raphtalia. When she tries it on, it reveals a shocking secret about her past...