Every once in a while in these vast United States, you come across an area so remote, so isolated, that the people of that area maintain a culture that is completely removed from the mainstream. The San Luis Valley in Colorado, where people still speak an archaic form of Spanish descended from a popular variant from about 400 years ago, is one example of that phenomenon. Another example is the Gullah people of the South Carolina and Georgia Lowcountry, who have retained more of their African heritage -- both culturally and linguistically -- than any other group of black Americans in the U.S. One thing is certain: You don't see too many films about them.

The Gullah were originally brought over as slaves to work the rice plantations in that Southern region; they came from an area of Sierra Leone, where rice was also the dominant crop. Unlike in similar slave-plantation setups in other areas of the South, though, slaves in the Lowcountry had minimal contact with whites, who mostly stayed away due to rampant malaria in the region, and following emancipation, the Gullah were basically left as the lone inhabitants of the area, maintaining their culture and language -- a creole related to the creole spoken in Jamaica -- there for hundreds of years.

Daughters of the Dust is a look at that culture, the story of three women making the transition from one of the South Carolinian sea islands -- traditionally a bastion of the Gullah -- to the mainland around the turn of the twentieth century. Made in 1991, it remains one of the only films ever to focus on the fascinating Gullah culture and people, and a critically acclaimed one at that.

The film, directed by New York City-born Julie Dash, screens tonight as part of the Blair-Caldwell African American Research Library's Seldom Screened: Black Directors series, at 6 p.m. tonight, for free. And if that's not enough to get you in, consider this: There will be free popcorn and drinks. What more do you want?