The Sultan of Zanzibar has a harbor infested with sharks, which makes it impossible for ships to trade with him. In an attempt to fix the problem, he brings twelve hippos into the harbor to keep the sharks away. His idea works well enough, but once the hippos are no longer a novelty and the people no longer feed them, they begin to starve. After the hungry hippos rampage through the city looking for food, Aban-Khan, the king's adviser, slaughters all the hippos except one, a little hippo named Hugo.

In the wake of a Supreme Court decision to outlaw the death penalty, California passes an initiative that designates San Bruno island as a dumping spot for first-degree murder convicts, free to do what they like except leave. The main camp of convicts is controlled by the tyrannical Bobby, who rules with an iron hand, and the women are used as sex slaves. A.J. and a group of more free-minded murderers have escaped and gone into hiding. When A.J. and his men liberate the women from Bobby's custody, tensions mount to an all-out confrontation for control of the island.