The main character, Luffy, is determined to become the Pirate King. After accidentally eating the Rubber Fruit, he gains the powerful ability of rubber elasticity, which becomes his weapon. After ten years of hard practice, he is finally able to fully control the power of his rubber body. At this point, he decides to set sail and head towards the legendary "Grand Line." However, he's a brainless guy with no navigational knowledge and can't even swim, having no idea where the "Grand Line" is. Thus, he begins his journey in a typical shonen manga style.