Few anime shows have had the kind of impact and legacy of "One Piece." Since debuting in 1999, the show has achieved what few manga and anime have, reaching over 1,000 episodes, getting over a dozen movies, breaking all sorts of records, and only increasing in popularity.

Unlike other long-running TV shows like "The Simpsons," or "Grey's Anatomy," "One Piece" has not fallen off in terms of quality. Nor does it have a "golden age," being based on a single story told by a single author who has long since abandoned his initial plan to end the story after five years. There are, of course, some all-time great episodes from early in its run that showed the promise of the story and made audiences fall in love with "One Piece." More recent episodes, however, have reached previously unthinkable levels of complexity and quality in terms of both story and animation, even as...