Monkey D. Luffy and the Straw Hat Pirates sail into a massive whirlpool and find a hidden city, the Ocean's Navel, guarded by giant sea monsters and ruled by the tyrannical Captain Joke. Luffy, Roronoa Zoro, Sanji, Nami, and Usopp get pulled into a standoff over a treasure said to grant any wish, alongside islanders Meroie and Hamu, who know what is really guarding it. This one-episode TV special aired between regular episodes and stands apart from the main story.