I'm trying to identify a sci-fi movie i saw as a child in the early
1960 at a saturday matinee. It was probably made in the 1950s. My
memory is that it had a name simialr to 'Invaders from Mars' but it
is not that film (Menzies, 1953). I think the plot was very similar,
though: people transformed one by one into zombies, with some
telltale mark, only one person recognizes it (I think also a child),
etc. However, my memory is that this film was in black and white, had
more naturalitic acting than 'Invaders from Mars.' and as I recall,
the invaders were hiding out some secret process in a chemical plant
or refinery, and near the end of the film the place blows up and
there's a blob-like thingie or two terrorizing the humans at that
point.

So does anyone remember a movie like this? Can anyone recommend a
source/method for trying to dig up stuff like this.

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