It's also a perfect example of what makes this such a special cartoon. "One Piece" slowly evolved from ... dream sequence where Yamato hears Ace talk about Luffy's dream while recalling reading ...

a pirate who was locked away on Level 6 of Impel Down but escaped during Luffy's invasion to save Ace, in order to lure Hancock to him and use her as a hostage against the World Government due to ...