There was a major Sci-Fi craze during the 1950’s, helped along by the UFO sightings that began after WW2. Another 50’s fad, a brief one, was 3-D movies. The 1953 cartoon “Popeye, The Ace of Space” was released in 3-D. Keep that in mind while watching the video.
This cartoon contains a couple scenes of “alien experimentation” that upset me greatly as a child, despite Popeye escaping unharmed (thanks to spinach, of course). Scanning through some of the later Popeye cartoons released by Paramount, it seems that someone at the Famous studio had a real sadistic streak that crossed the line from cartoon mayhem into something darker and more disturbing.
See my “Brutal Bluto” post. Popeye was a comic strip, created by Elzie Segar in 1929. The cartoon came along in 1933.
I find it interesting that Popeye sets his normal age back at 40! That would be roughly correct, according to when he was created by the Max Fleisher studios, wouldn’t it? Also, the aliens aren’t “little” green men, but big and burly, like Bluto. Now that you mention it, there was a lot of violence in the Popeye cartoons. The other thing that became clear to me later in life is that Bluto was clearing trying to rape Olive Oyl, with Popeye always coming to her rescue. Sometimes she acted like she wanted his attentions, like in the clever parody “The International,” but mostly, he was extremely rough with her.