This is the first appearance by Ghidorah. When a huge meteor lands on earth out pops the giant three headed monster who proceeds to destroy all in his path. Add to this a beautiful Princess who claims to be a Martian and the assassins who want to kill her, and you have one hell of a movie.
The effects by Eiji Tsuburaya are top notch and the action, once it starts never lets up for a minute. Akiko Wakabayashi is simply gorgeous as the Princess/Martian. The monster battles are top notch and one scene in particular I will never forget is when Mothra attempts to get Godzilla and Rodan to join forces. I admit I have to laugh at that one.
If you love Japanese monster flicks as much as I do I cannot see you missing this one, and if it's been a while since you've seen it, pull it out of the closet and watch it again. Very enjoyable.