The Straw Hats visits an island, known as Mecha Island, where a fisherman sings an old folk song about a Golden Crown. Searching for that mysterious treasure, they find a hidden entrance into the island. The island's leader, Ratchet, impressed with the find and in search of the Golden Crown himself, invites the crew to join him in his search and the crew along with Ratchet and his henchmen enter the cave. As it turns out, the islands true form, is that of a giant turtle. Ratchet, who had known this all along, uses his mechanical castle to take control of the turtle, in order to use it, to take over the world. Now the Straw Hats have to stop not only Ratchet, but also the helpless turtle, from crashing into a nearby island.
One Piece - The Mysteries of the Mechanical Island (ONE PIECE THE MOVIE ) is a 2006 animated film directed by Kōnosuke Uda. It is the seventh film taken from the manga and anime series One Piece by Eiichirō Oda. The film is located before the arrival of the crew at Water Seven.The title of the film literally means "The giant mechanical soldier of the castle of Karakuri". In the trailer of the film there are fights then not included, against robots did not appear. Moreover, it is possible to see Rufy seriously injured and bleeding, which in the film does not happen.