The funny old lady whom the Straw Hat crew comes across by chance on the open sea promises to give them treasure if they agree to accompany her to the mecha island. However, instead of a treasure, it is a defense system based on a multitude of small mechanisms that awaits Luffy and his crew. Intelligence and strength will weigh with all their weight in the fight between Luffy and the terrible Ratchet, the lord of the island who is passionate about mechas and ready to conquer the world! What will happen to the Straw Hat crew? And how will Luffy react?!