When a mysterious monster rises from the Mekong River and attacks Bueng Kan, it cuts people off from the outside world. Officials and people in the area, including Chinese scientists who accidentally came to conduct research in Thailand, all forces must be mobilized to catch this crazy monster before it's too late.

Greedy sailors capture a giant lizard off the coast of Ireland and sell it to a London circus. Then its mother shows up.

A portion of the tail of a prehistoric reptile is discovered in Denmark. It regenerates into the entire reptile, which proceeds to destroy buildings and property and generally make a nuisance of itself. It can fly, swim, and walk, and has impenetrable scales, which makes it difficult to kill.

Earthquakes in central Korea turn out to be the work of Yongary, a prehistoric gasoline-eating reptile that soon goes on a rampage through Seoul.

A blazing fire rips its way through Bear Valley National Park. As the firefighters try to contain it, the animals are being forced out of their habitat including a beast that was better left undiscovered.

A detective and his cowboy friend team up to stop a mad scientist who is stealing the bodies of murdered wrestlers, and bringing them back to life while electronically replacing their minds with those of animals to make them stronger and live longer. Posing as a successful masked wrestler, the cowboy quickly attracts the attention of the scientist and his henchmen as their next experimental subject...