The story begins with Monkey D. Luffy, who barely escapes after being trapped in a barrel after being trapped in a whirlpool. He seems like an ordinary innocent boy, but it would be a big mistake to take him lightly. Luffy is no ordinary person, but a pirate whose goal is to find the world's greatest treasure, "One Piece," and become the "Pirate King." In fact, before his death, the former Pirate King, Gol D. Roger, announced to the entire world that he had hidden all his treasure somewhere, and whoever found it would become the new king. Then what happened was that thousands of pirates set out in search of that treasure, and many never returned. Luffy initially had neither a ship nor a crew, but he possessed a unique superpower and an unwavering spirit. With his ever-present smile and spirit, Luffy joins forces with new friends and embarks on an adventure that happens once in a century.