One Piece: Taose! Kaizoku Ganzack  

One Piece: Defeat Him! The Pirate Ganzack, ONE PIECE 倒せ!海賊ギャンザック

As they sailed on their tiny vessel, Luffy, his companions Zoro and Nami were hungry. Suddenly, a massive creature attacked them, taking Nami captive while Luffy and Zoro washed up on shore. There, they encountered Medaka, who shared the tragic tale of her island home. Ganzack, an infamous pirate, had kidnapped all the men in the village and made them his slaves, including Medakas father. Now, Luffy, Zoro, and Medaka must venture into Ganzacks stronghold to save the villagers and rescue Nami.

One Piece: Taose! Kaizoku Ganzack is based on the OVA of the same title, which was the animation debut of the One Piece series.