Several men decide to look for an opal and when they discover it, they steal it and bring it back to Japan. It turns out the Opal is actually an egg and it soon hatches.
The treacherous expedition which has already cost the life of one man, now brings a new terror to Japan in the form of a huge reptile monster that emits a killing frost from it's tongue and a destructive rainbow that emits from it's back.
Meanwhile the rocket was sent off in hits a meteor and before you know it Gamera is back on Earth. The two monsters battle each other while the army tries to find a way to rid the Earth of both creatures.
There are a lot of dark elements here including double cross, murder, greed and lust. Interesting stuff for a Japanese monster film.
the Blu-ray looks fantastic and is recommended for monster fans.