This movie is a lot - but ultimately disappointing
First I want to express my admiration for this little movie. It is very fascinating from the get go, and although all the tropes and clichés are exhausting, you can forgive all that to a movie made in 1963.
I like some of the more interesting camerawork, but I am not fan of all the unnecessary dutch angles and such, so it is a bit of a hit and miss. There are a couple of places where the camerawork was unexpectedly great - good enough for even me to notice (usually I don't).
Then there were some weird, completely unnecessary 'errors', as in jumpcut in the middle of a straight shot, usually the moon poster. Why would they introduce a jumpcut where it's completely unnecessary? I guess for camera to pan to, and then from the poster was done separately, but often the pan didn't start from some scene from before, but from a jumpcut already pointed at the poster, so it makes no sense.
The acting performances are sometimes a bit clunky, but all the actors have some kind of weird charisma, and other times, they are really good.
The amazing thing of a movie made in early sixties, is how well it keeps your attention - I bet even the 1-second attention-span modern people could watch this without feeling bored. The pacing feels natural and yet there's almost never a dull moment.
The ending twist was straight from the Twilight Zone, and any modern movie viewer can see it coming from miles away.
There are some pretty silly, unbelievable things that bring the movie down a few notches, and the overall stupidity of 'Extra-Terrestrials being evil monsters with no humanity' must have been groan-inducingly stupid even for 1963. Why is it so rare in these movies to see good people that live on other planets?
One very silly thing was the whole 'kids react adversely to her'-thing. Why would that make her so sad, when she is supposedly trained to kill people? The lives of some alien kids should mean nothing to her.
If SHE can 'love' and be so emotional and snowflakey about everything, why is the secretary so cold and emotionless? You can't have it both ways - either this kind of 'space travel' gives you 'human emotions', or it doesn't. The ending, thus, makes no sense. The secretary should be able to feel some kind of sympathy/empathy/guilt/etc.
Also, 20 years? Twenty years is NOTHING in the cosmic scale! The actual Extra-Terrestrial visitors have been here even before Earth was habitable - they had bases on the moons, that were more stable at the time (yes, Earth had two moons, and it was the other moon exploding and raining on the planet that ultimately sank Atlantis and brought the ice age).
So, my point about the kids is - why would ALL of the kids behave the same way, move backwards in an orchestrated, practiced, synchronized motions?
Are you telling me kids are more sensitive than adults, but there are no exceptions? There MUST have been some 'thicko' kids that don't feel anything about her, and would just stand around screaming insults to the weird, staring auntie. Come on, ALL kids are super sensitive? That makes no sense. (A weird sidenote - the kids' faces look weirdly 'adultlike' compared to modern people, don't they?)
The baby I can understand, but some youngster tough guy wannabe bully fatsos? No WAY they would be 'sensitive' enough to feel anything about this woman.
So how do they manufacture/fabricate their bodies? I mean, you can't just materialize a body out of thin air just by concentration, no matter how much you train, and still be able to be a lowly enough soul to be able to kill. When you reach the level where you can just form a physical body with pure thought, you are no longer anything recognizable as 'bipedal human', you are a third level entity that hasn't required a body for any reason for a really long time.
The eyes open-thing - some people do sleep their eyes open, but then there's REM-sleep, which would look wild that way. The eyes would not just be staring up.
Also, if sedation makes them 'lose concentration', why does sleeping NOT make them lose concentration? Isn't it the same thing, except natural vs. artificially induced?
Do they 'materialize' naked? Or why do the clothes not disappear? Do they create a fully perfect human body by pure thought but can't create clothes? Or do they arrive naked and steal clothes somewhere, in which case, there should be a 'clothes robbery epidemic' going on, which should raise a few eyebrows!
Why did the cloroform not work until the secretary fell all the way to the ground?
If 'losing focus' means 'disappearing', then why don't they disappear more often, since no one can keep focus all the time, why does this 'loss of focus' sometimes appear as 'not blinking' and 'metal skin that doesn't get burned'?
I don't care what planet you are from, if you are on Earth in a functional human body, the surface of that body WILL get burned if it touches 250 degrees metallic stove, oven or casserole dish!