Season 1

Jyugo, Uno, Nico and Rock make an attempt to escape, only to get caught by Hajime Sugoroku. The group later spends some time bugging Hajime and indulging in idle chat. The Warden, Momoko Hyakushiki, returns and discusses Jyugo with Hajime, telling him not to underestimate him.

Hajime Sugoroku discusses the backstories of the four inmates of Cell 13 with the Warden.

Seitarou Tanabata has difficulty dealing with Cell 13 due to their persistent bullying and appeals to Hajime Sugoroku for help. Tsukumo, a repeat offender and escapee, is transferred to cell thirteen but moved to cell eleven after conspiring to break out with Jyugo. Meanwhile, Nanba Prison prepares for New Year's.

The New Year's Tournament kicks off, with Building 13's Cell 13 being chosen as one of the participates. The first round includes all guards and inmates, the second has Yamato Godai and Rock team up while Seitarou Tanabata and Uno team up for Round 3.

Uno continues his match against Honey and Trois and ultimately wins. Hajime Sugoroku and Nico face against Samon Gokuu, Qi and Upa in the following Spinning-top round.

The final match of the New Year's Tournament begins; Kenshirou Yozakura & Musashi vs. Hajime Sugoroku & Jyugo. Hajime seems to be doing fine with his match, but Jyugo ends up in a bit of trouble against his opponent, whom he seems to have some history with.

Sometime before the second round of the New Year's Tournament, Tsukumo is visited by Hanzou Hattori. During the visit, Tsukumo's past is revealed.

The battle between Jyugo and Musashi continues on as Jyugo goes berserk and let's loose his power after hearing Musashi mention the man that placed the shackles on him. The Warden orders the guards, Hajime Sugoroku, Kenshirou Yozakura, Samon Gokuu, and Kiji Mitsuba, to contain the two inmates.

Hajime arrives back after his three day suspension. Jyugo and Musashi, while locked away in underground chambers, are allowed by Hajime and Kenshirou to communicate with each other via handheld transceivers. Musashi sheds some light on the Man with the Scar to Jyugo.

While Hajime is on his three day suspension, Kenshirou Yozakura, Kiji Mitsuba, and Samon Gokuu take turns each day to supervise Building 13. Jyugo finally returns to Cell 13 and apologizes to them for all he's hidden from them.

The stone oven that Rock wanted, for Building 13 winning the New Year's Tournament, is finally installed. Nico also gets a game room.

Musashi discusses more of his past prior to meeting the Scarred Guard with Kenshirou Yozakura. Uno gets everyone from the New Year's Tournament together to play in the game room he got for Cell 13's victory in the tournament. Later, Jyugo leaves Cell 13 for some fresh air at night, only to encounter Elf.

Jyugo meets Elf, who threatens to use those close to him as experiments, just like him and Musashi. Following the next night, Cell 13 breaks out of their cell for fun, but Jyugo intends to really escape so Elf will chase after him and leave the others be. Hajime, however, is determined not to allow Jyugo's passage.