Yoshi, a troubled teenager, is sent by his grandfather to Seijun, a highly renowned tattoo artist. Against all expectations, the boy masters the art of tattooing, including the complicated Tebori technique. Ten years later, Seijun reveals a great secret to his apprentice: his clients are from the yakuza, the formidable Japanese mafia. Each tattoo they bear has a specific meaning, often to do with the murders they've committed. When Yoshi discover that his friend is tattooed with the same strange design as one of the yakuza bosses, his whole world turns upside down...