The American Film Institute's Silver Theatre screens a new 35mm print of Robert Wise's 1951 sci-fi classic The Day the Earth Stood Still, about a visitor from another planet who tries to warn the people of Earth about the dangers of atomic experimentation for the entire galaxy. Forget renting the Keanu Reeves remake -- this is the one to see. Saturday, Sept. 11, at 5 p.m., and Sunday, Sept. 12, at 5:45 p.m. AFI Silver Theatre, 8633 Colesville Rd., Silver Spring. Tickets are $10 general admission. Call 301-495-6720 or visit afi.com/Silver.