One Piece

Season 1, Episode 32

Episode Title: Witch of Cocoyashi Village! Arlong's Female Leader!

Air Date: 2000-07-19

Overview:

Zoro is captured by the fishmen after Usopp and Johnny ditch him, and it's revealed that Nami was part of Arlong's crew the entire time. When a group of Fishmen attack Cocoyashi Village, Usopp comes to the rescue.