The once famous and well respected scientist Zorndyke has bred a new genre of living being, one that thrives on the oceans and lives to destroy humans. Zorndyke believes it is time that the humans were relieved of their rule of the earth. It is up to Blue Submarine No. 6 and the rest of the Blue fleet to put an end to Zorndyke's madness and creations. (Source: ANN)

Taka (technically Tamahome) and Miaka are now happily married and only six months before their new family would be born, but an obsessed girl named Mayo would do anything to make Taka hers. She enters the world of the Four Gods, determined to win Taka's heart and be the new priestess.

Ever since the fall of the DARK organization, Jiro has been wandering everywhere and wondering if he would ever see Mitsuko again or not. During his journey Jiro meets a beautiful girl named Rieko who is protecting Akira, a little boy from the evil Professor Gill. Ironicly, he's the son of Professor Gill, but he is also the key to Gill’s menacing secret weapon and his plans to conquer the world. (Source: ANN)

Hatsuki is a highschool student living with her sister, Hatsumi, who she has a huge crush on. On Hatsumi's 16th birthday, she is suddenly surrounded by a green light and disappears in front of Hatsuki. She manages to follow Hatsumi with the help of a being resembling a fat baby chick (literally), ending up in a place called "The Great Library", which is full of different worlds stored in books. Hatsumi wasn't there, though, so the search for Hatsuki's great love begins and involves traveling from book to book. (Source: AniDB)