There were a lot of 50's sci-fi movies. They were big draws for the Drive-in theaters. A lot of them were crappy even back then. This movie and 'The Day the Earth Stood Still' stand out, and both have aged well in their own way. From the very beginning with its eerie theremin musical score (which still sounds weird since theremins are hardly ever used) Forbidden Planet takes you where no man has gone before. Speaking of Star Trek there's so much material in this film that got into Star Trek TOS its like a pilot for the series; from the interactive captain/first mate/doctor, the mad scientist, alien beings, babe in short skirt, computer intelligence; it is all de rigeur now but this was the first of its kind. Besides, it has good acting and well-done artwork which even today evokes a certain awe at the imagery. Consider how the huge Krell machine is successfully depicted with some real depth. I saw this as a kid (at a drive-in :0)when it was a new movie and it scared me. Of course every movie that was even vaguely scary did back then but I remember being real worried about the invisible monster. Forbidden Planet is a movie a sci-fi fan can watch several times and find something new with each viewing.