Itou Kaiji is a bum who steals car emblems and slashes tires on a regular basis. However, one day, this routine changes when a man in a trench coat pays him a visit. The man reveals himself as Endou, a debt collector, who has come to claim an unpaid loan of 300,000 yen, which Kaiji had previously co-signed with his co-worker, Furuhata Takeshi.

Because of Takeshi's disappearance, Kaiji is left with an overwhelming balance, but is given the chance to gamble against other bankrupt bums aboard a boat — each gambler is loaned additional money, giving them a chance to pay their dues or become in even deeper debt.

Kaiji accepts the challenge in hopes of repaying the compounded debt of 3,850,000 yen and, with luck, winning additional cash...

[Source: Crunchyroll]

After the events at the Starside Hotel, Kaiji Itou finds himself living his miserable lifestyle once again. Captured by the Teiai group to which he owns a lot of money, he is thrown into an underground forced labor camp where he must pay off his debt by doing harsh manual work. Kaiji becomes desperate as it is expected that he lives in this hellhole for the next 15 years.

[Source: Anime News Network]

Chuukan Kanriroku Tonegawa is a spin-off of the Kaiji series, which follows Tonegawa, the right hand man of Kazutaka Hyoudou, the president of the Teiai Corporation and owner of numerous gambling tournaments. After Hyoudou is getting bored with his life, he orders Tonegawa to organize a so called "game of death" as it is his and his subordinate's job to keep the president in a good mood. Tonegawa must cooperate with his subordinates in order to make the president happy and what follows is a humorous story of his interactions with his subordinates and other characters of the Kaiji series.