9, a hidden organization under the world government as the Straw Hat Pirates are accused of an attempted assassination on Iceberg, the leader of Water Seven and the Galley-La Company. The season centers around the intrigue of Water Seven as Nico Robin leaves the crew to seemingly join up with Cipher Pol No. However, the Japanese analog broadcasts are still in 4:3 fullscreen format. The press release also mentioned that the episodes would be released in 'HD' hinting at a possible Blu-ray release, but made no direct mention of the high definition disc format.

The press release stated that the episodes would be featured in 16:9 widescreen. In October 2011, Funimation announced they had acquired this season, along with the entirety of the previous season for release as part of their own US 'Season Four'. Twelve DVD compilations, each containing three episodes, were released by Toei between January 10 to December 5, 2007.

They initially ran from Apthrough Apon Fuji TV. The episodes are based on Eiichirō Oda's One Piece manga series, and adapt the 34th through 39th volumes of its source material over thirty-five episodes.

Its episodes are directed by Kōnosuke Uda and Munehisa Sakai and produced by Toei Animation. The eight season of the One Piece anime series contains The 'Water Seven' Chapter.

Added chapter 2 season 8 episode 30