After surviving another undersea battle with Zorndyke’s forces, the crew of Blue Submarine No. 6 returns to base for repairs. While on base, Tetsu continues to display his trademark lack of concern for authority and continues to annoy Mayumi.

The poles are shifting and most of the Earth’s land is now underwater! The scientist Zorndyke has created a race of beast people to challenge the humans for global supremacy. But who is the real enemy — Zorndyke or humanity itself?