The Straw Hats, having been left by Robin, uncover the real motive behind the actions of the CP9 assassins and try to stop them from using the most destructive weapon of the ancient world.

Nico Robin is blamed for the attempted assassination of the mayor of Water 7, and the Straw Hats try to clear her name while uncovering information that the members of CP9 might be the real culprits.

"When Crocodile's evildoing is exposed, the rebellion that will destroy Alabasta just might be averted... But the Baroque Works will do everything in their power to make sure that doesn't happen--even if they have to kill Princess Vivi! The Straw Hats are in for the fight of their lives to keep this evil Croc from getting his way!"--Cover.

As the Straw hats leave Vivi and Alabasta behind, they discover a stowaway on board who wants to become a crew member! But can they trust this former Baroque Works agent?! Whether friend or foe, they'll be needing all the help they can get when their Log Pose suddenly points up to the sky!