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Paris Qui Dort (Paris Which Sleeps, aka At 3:25), an early short film by René Clair: a mad scientist uses a time-freezing ray on Paris, pausing everyone in their day-to-day life throughout the city. Everyone except for a random handful of people who happen to be up in the air at the time, who decide to take advantage of the perfectly still city. Proto-surrealist sci-fi with a dash of percolating social commentary.
I learned about this one from The Invention of Hugo Cabret, an excellent children’s historical fiction novel about early cinema, magic, automata, and Georges Méliès. Worth reading if you’re into any of those things.