Four men are assigned to Nanba, the world’s most formidable prison. Jyugo, a man who attempted to break out of prison and ended up extending his jail time; Uno, a man who likes to gamble with women; Rock, a man who likes to get into fights; and Nico, a man who likes anime. A super exciting action comedy about the daily lives of the prison’s inmates and guards.
Jyugo makes a routinely escape attempt and is caught by Hajime while he's napping in the Guard's room with Kuu. All the inmates and guards seem to be going through a typical and ordinary day, much to the chagrin of Mitsuru Hitokoe, who wants something exciting to happen during Part 2 of the anime.
Hitoshi Sugoroku starts working as a Nanba Prison guard, much to Hajime's surprise. Uno and Rock don't believe that the "kind and cute" Hitoshi is the little brother of the "vicious gorilla" Hajime and try to disprove that they're siblings by testing Hitoshi's abilities as they escape.
Rock challenges Samon Gokuu to test his strength and is defeated with little effort. The Warden leaves to attend a meeting at the Police Department HQ. Mao Nimaijita accuses Samon about potentially following in his older brother's footsteps. Yamato and Rock return to Building 13 after spending time at Building 5, and while not themselves, they attack Hajime and Jyugo.
Jyugo is saved by Tsukumo from an out-of-control Rock. Meanwhile, Hajime deals with Yamato, who's in the same state as Rock. After finding a talisman on the two of them, Hajime and the others recognize the talismans belonging to Building 5. Hajime decides to go investigate the matter, and with much convincing on Uno's part, takes Cell 13 (except Rock) with him. He leaves Building 13 surveillance to Mitsuru Hitokoe. Mitsuru tells Hajime that they contacted Building 5, but nobody has been responding.
Jyugo, Uno, and Nico wind up in an underground cell that happens to be holding Upa and Liang. The two inmates from Building 5 inform the trio that Building 5 has been compromised by the former Nanba supervisor, now inmate, Enki Gokuu. The five inmates escape their cell, thanks to Jyugo, and head off to find Hajime and Samon Gokuu. Along the way they find Honey and Trois locked in a cell.
The team of inmates retreat into an abandoned office where Jyugo discovers confidential inmate files about himself. As they advance, they Liang and Upa send them ahead and stay behind to fight a possessed Rokuriki before being confronted by their former boss, Hachiman.
The fight between Liang and Upa against Hachiman continues. Nico shows up out of nowhere and greets Upa, moved by his last line in the previous episode. Qi recalls events from his past when he joined up with Hachiman. Nico intervenes in the fight to save Upa, meanwhile, Uno freaks out about how they all lost sight of Nico. During the fight against Hachiman, Nico's medicine starts to wear off, and an alternate persona appears to take over.
Uno explains to Honey and Trois that when Nico's medicine wears off he goes out of control. As Nico's alternate persona awakens, he fights Hachiman. In the meantime, Liang and Upa restrain Daisen Rokuriki and destroy his talisman. Qi interrupts the fight and while Nico attacks him, he injects Nico with his medicine, rendering him unconscious. Hachiman feels as though he has won, however, to his, Liang, and Upa's surprise, Qi injects poison into Hachiman's leg. While Hachiman is unconscious, Upa, Liang, and Qi talk. Hachiman eventually regains consciousness, and tries to fight the trio, but he's taken down by a group attack.
Upa wonders if someone other than Enki is involved in the situation. Meanwhile, Jyugo and his group reach level 2 where they are confronted with numerous Jiang-Shi dolls. As Trois explores the area, they encounter Ruka Gojou and other guards with talisman on their foreheads, Daisen Kokoriki and Daisen Youriki. Trois tries to defeat him with a handmade a flame-thrower he made with leftover parts. Just as they think they are free, Ruka Gojou appears and captures Jyugo.
Jyugo has been captured by Ruka Gojou, but is saved by surprise attack from Trois. Honey gets frustrated with Jyugo's uselessness and wants to leave him behind. Eventually, Ruka, Daisen Youriki and Daisen Kokoriki catch up to the group and Jyugo is caught by Youriki. While trying to help Jyugo, Uno is restrained by Ruka. Though initially reluctant, Honey decides to help. The two inmates of Building 3 decide to repay their debts to Jyugo and Uno, and deal with Ruka and the Daisens. After managing to subdue them, Ruka surprisingly comes out unscathed, now prepared to fight them seriously.
As Ruka begins to fight seriously, Trois and Honey pursuade Uno and Jyugo to go ahead while they continue fighting but Jyugo eventually returns and defeats Ruka with his blades. Kokoriki and Youriki later arrive and try to arrest the escaped inmates. As they escape, Uno, Honey and Trois come up with a plan while Jyugo begins to make his way to Hajime.
Enki realises the prisoners have escaped as Mitsuru and Kenshirou begin questioning the situation. Meanwhile, Trois and Honey free Kiji who takes care of Daisen Kokoriki and Daisen Youriki before defeating Ruka. Jyugo finally finds Hajime before freeing him and Samon from their cells. Kiji handcuffs the inmates, but they are suddenly confronted by a hoard of surveillance dolls as are Jyugo and Hajime.
