First Sea (ひとつめの海, Hitotsume no Umi) is the 4th Night of Adventure of Sinbad anime. This episode is a TV edit (with minor changes) of the 3rd OAD which came out bundled together with the fifth volume of manga, entitled The Capture of Dungeon Valefor - Part One (迷宮ブァレフォール攻略篇・前篇, Meikyū Varefōru Kōryaku-hen - Zenpen).