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The movie follows the story of Larry Daley (played by Ben Stiller), a down-on-his-luck divorced father who takes a job as a night guard at the American Museum of Natural History in New York City. He soon discovers that the museum's exhibits come to life at night, thanks to a magical tablet from ancient Egypt. The main exhibit, Teddy Roosevelt (played by Robin Williams), becomes his ally, along with other historical figures and artifacts. While you are looking for a download link
If you are looking for the Night at the Museum series with Tamil audio or subtitles, there are much safer, legal alternatives that offer high-definition quality: Teddy Roosevelt (played by Robin Williams)