A wild animal attacks six medical students on a weekend hike in the woods. One by one, they become infected with a “feral disease,” turning them into rabid, bloodthirsty creatures, and the vacation becomes a nightmare as they fight to survive each other.

The U.S. Navy's special group "Blue Water" builds a half-shark, half-octopus for combat. But the sharktopus escapes and terrorizes the beaches of Puerto Vallarta.

When the prehistoric warm-water beast the Crocosaurus crosses paths with that cold-water monster the Mega Shark, all hell breaks loose in the oceans as the world's top scientists explore every option to halt the aquatic frenzy. Swallowing everything in their paths -- including a submarine or two -- Croc and Mega lead an explorer and an oceanographer on a wild chase. Eventually, the desperate men turn to a volcano for aid.

Qian Cheng, the boss of the pharmaceutical company, has invested in the establishment of a biopharmaceutical research laboratory located deep in the jungle. By modifying the shark gene to develop a new type of anti-cancer drug, but when the drug is about to be put into mass production, a huge crisis also came quietly: due to the change of the shark's gene, the gene mutation was fierce and showed the characteristics of other organisms.