Do not be tricked. This movie has neither frankensteins monster nor godzilla.
German scientists, who cant be Frankenstein because Frankenstein was Switzerlander, finds a hear that supposedly belonged to Frankenstein's monster and survived. The germans take it away from him and swims to Japan. Wait ive seen that before. Germans give it to Japanese soldiers in a submarine exchange. The Japanese says that Frankenstein was destroyed but his heart has survived because its immortal. There is also a child that appears to not know how to speak. but he steals food and eat live animals.
They campture the boy and use it in lab to "help" him. Around that time a monster from underground emerges looking frightening but not doing anything on screen. The kid looks hideous and is amazed by television.
They find a doctor who worked on the hear and he tells them about the frankensteins monster. the whole story of him being immortal. the boy grows up rapidly, and they notice that his chains become to small for him, but clothes seems to grow with him though. his only pleasure is eating. The monster is annoyed by camera flashes as tv tries to film him and escapes the facility. hes way too big to fit in it anyway. well he is in no hurry though as he stops to eat stuff. Apparently the person is 3 storeys high now. so he goes on and talks to a woman who was kind to him.
They army goes on to search for it but has no success in that, while the kid keeps growing bigger. Meanwhile the other monster return and this time actually does some wreckage. The scientists figure out a way to lure the new frankensteins monster by placing some food as a trap, but he doesn't go for it. Howeer after few days of starvation he seems to go after it after all. The scientists then decide to go at it alone and put him to eternal sleep. by poisoning his eyes. However they are attacked by the second monster instead, who almost kills the woman. however the boy comes to rescue and fights the monster. the rest of the film really is just cheesy fight. reminds me of those godzila sequel fights.
Story: 2/10. basicly bad. very bad.
Acting: 2/10. basicly bad. very bad.
Sound: 3/10. a bit better than story and acting.
Sci factor: 0/10. seriuosly?
Lasting Appeal: 0/10. No, this doesnt work at all.
Overall rating: 2/10.