Day of the Triffids(1962)

"A shower of meteorites produces a glow that blinds anyone that looks
at it. As it was such a beautiful sight, most people were watching,
and as a consequence, 99% of the population go blind. In the original
novel, this chaos results in the escape of some Triffids: experimental
plants that are capable of moving themselves around and attacking
people. In the film version, however, the Triffids are not
experimental plants. Instead they are space aliens whose spores have
arrived in an earlier meteor shower. " -Precis by Imdb

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