Don't know the name of the scifi movie
This movie is about a grandfather that is passing down his secret to his grandson. The grandfather is well known for his monster movies. In the movie, every 10 years (in a small town) a monster will show. The monster has to be killed so that the townspeople will not remember the monster and the town goes back to the original town. The monster is not killed in the same manner every time. His grandson doesn't believe him at first. They end up killing the monster and the grandson takes over his grandfather's job killing the monster.
