The Going Merry is stolen and Nami is kidnapped by the Trump Pirates, so Luffy, Zoro, Usopp and Sanji team up with the Thief Brothers Borodo and Akisu to retrieve their precious crewmates from Clockwork Island.

Upon entering the Grand Line, the ship is swallowed by a giant whale, inside of which they discover a strange place. In addition, they are not the only ones there.