"You've disturbed something that should have been left alone." Lee Shin-hyuk, codenamed "Ventablack," is the Korean leader of "55" - an elite special operations unit selected from the world's top black agents. One day, his younger sister Sumin, who dreamed of becoming a K-pop idol trainee, is murdered in South America... and the world tries to cover up this fact. After abandoning everything to investigate his sister's death, Shin-hyuk confirms that the international drug cartel "XICA" is likely behind it. Subsequently, for his revenge, he deliberately approaches his targets by becoming a bodyguard for "Yoo Chae-won," a global K-pop star whom they were originally targeting. Finally, he plunges into Brazil's "Favela" - a land of death forsaken even by God...