One Piece: Baron Omatsuri and the Secret Island

Informed by the Thief Brothers his ship has been stolen by the Trump Kyoudai (Trump Siblings) who have set up base on Clockwork Island. Monkey D. Luffy, Captain of the Going Merry and aspiring Pirate King works with his crew - Ussop, Zoro, Sanji and Nami to battle their way up Clockwork Island to reclaim their ship.

There once was a pirate known as the Great Gold Pirate Woonan, who obtained almost 1/3 of the world's gold. Over the course of a few years, the pirate's existence faded, and a legend grew that he disappeared with his gold to a remote island, an island pirates continue to search for. Aboard the Going Merry, Luffy and his crew, starved and reckless, are robbed of their treasure. In an attempt to get it back, they wreck the getaway ship, guided by a young boy named Tabio, who's a captured part of El Drago's pirate crew. El Drago's love for gold has driven him to look for Woonan's island, and thanks to Woonan's treasure map, he finds it. During this time, Luffy's crew have been split up, and despite their own circumstances, they must find a way to stop El Drago from obtaining Woonan's gold.

The crew salvages a treasure chest from a sinking wreck, but inside turns out to be an old lady hiding. To get the Straw Hat Pirates to take her home, she promises them the treasure of a golden crown on her island, Mecha Island. When they arrive, their ship is first attacked by the lord of the island. But later he decides to use the pirates to help him solve the riddle of the Golden Crown.

The Straw Hats encounter a city in the middle of a whirlpool, called the Ocean's Navel, that is being destroyed by giant monsters. These monsters supposedly protect a treasure capable of granting wishes, but in the process of defeating these guardians, the crew ends up releasing another evil. (aired after Episode 53)