YMMV / 20 Million Miles to Earth

• Accidentally-Correct Writing: At the time this movie was made, Venus was normally depicted in sci-fi stories as a swamp or jungle world. Here it is correctly described as being inhospitably hot, with a poisonous atmosphere and lethal levels of sulfur. Soviet space probes wouldn't confirm that Venus was like this until 1961. Of course, the movie didn't get everything right—as far as we know, there is no life on Venus.
• Designated Hero: While it's pretty clear that none of the human protagonists are evil, many of them are friendly and helpful- to each other, at least. When it comes to Ymir? Not so much. Not only do humans take the Ymir from his home in the first place, but there are many moments that show that while they talk about caring about the alien, they seem to be too fascinated by its alien qualities to notice it's screaming in fear or pain more than half the time. In fact, when the alien finally is killed the lead couple seems more interested in going on a date at a restaurant than anything else. Only General McIntosh and Dr. Uhl seemed to truly understand (and care about) the tragedy that had just transpired. Ray Harryhausen even agrees that the Ymir is actually a sympathetic creature.
• Heartwarming Moments: The Ymir making friends with a goat (technically a lamb).
• Older Than They Think: A mishap causing the power to go out and a giant creature to awaken and break free and go on a rampage, also happened in a 1940s Superman animated film, "The Arctic Giant". This is not the first time that same animated short seemed to give inspiration to Ray Harryhausen.
• The Woobie: The Ymir. It attacks people and injures some animals but only either out of instinct or fear from being attacked first and stuck in a hostile environment where every living being seems keen on killing it. It's not hard to feel sad over its death.

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