As a child, Monkey D. Luffy dreamed of becoming the King of the Pirates. But his life changed when he accidentally gained the power to stretch like rubber at the cost of never being able to swim again! Now Luffy, with the help of a motley collection of pirate wannabes, is setting off in search of the "One Piece," said to be the greatest treasure in the world.

The Straw Hats have infiltrated the Tower of Law to save Robin, but they still need a special key to release her. One of the CP9 assassins holds the right key, but Luffy and his crew may have to defeat them all. Can the Straw Hats thwart CP9 and rescue Robin?