The game follows the story of Kazuma Kiryu, a yakuza whose life changes when his boss, Sohei Dojima, attempts to violate Kazuma's childhood friend, Yumi. When the yakuza boss is murdered by Kazuma's best friend, Akira Nishikiyama, Kazuma accepts blame for the murder, and is imprisoned for 10 years. During his incarceration, Kazuma is expelled from the Tojo clan and his fiance, Yumi, goes missing. After his release, he learns that ten billion yen has been stolen from the Tojo clan, and the entire Japanese underworld is now searching for the lost wealth. Kazuma asks a former boss, Shintaro Kazama, about Yumi's disappearance, but Nishikiyama shoots Kazama after he reveals that Yumi was connected to the lost money. Kazuma then has to escape from the Tojo, who now regards him as an enemy. His escape is aided by a detective named Makoto Date who had been investigating Kazuma ever since the death of Dojima, and is now investigating the murder of Chairman Sera from the Tojo clan.