Forty years ago today, SupervisorHarvey Milk and Mayor George Mosconewere gunned down at City Hall. The Castro Theatre is marking that anniversary with a free screening of “The Times of Harvey Milk,” and there’s no better place to see this movie, as many of the events depicted took place near the movie hall.

The film tells the story of Milk’s life, a San Francisco supervisor who was the first openly gay elected official in California history.Directed by Rob Epstein, the film won the Academy Award for best documentary and has gone down in history as a classic, telling the story of Milk and the emerging gay rights movement.

For this special screening, admission is free. But if you want to stay for the second feature, the 2008 biopic, “Milk,” starring Sean Penn, you’ll have to pay the Castro’s usual $10-$13 admission price.

“The Times of Harvey Milk”:5 p.m. Tuesday, Nov. 27. Free. Castro Theatre, 429 Castro St., S.F.www.castrotheatre.com