Following the death of his parents, Aslan Jade Callenreese, known as Ash Lynx, was raised by the notorious mafia boss Dino Golzine. Now seventeen and the head of his own criminal organization, Ash is propelled by the dying words of his brother Griffin, who repeatedly whispered "Banana Fish" before succumbing in the Iraq War, to embark on a perilous investigation. However, his inquiry is abruptly interrupted when Dino's enforcers raid Ash's secret base located in an underground nightclub. Amidst the chaos, Ash encounters Shunichi Ibe and Eiji Okumura, two Japanese photojournalists documenting street gangs, through the connection of his friend Skip. Despite a cautionary warning from Shorter Wong, Dino's forces capture both Skip and Eiji. With no other option but to confront his dark history in the underworld, Ash launches a mission to rescue the abducted journalists and reveal the secrets behind the mysterious Banana Fish.