ANN E.W. STONE WAS MOSTLY just looking for new office space as she scouted Old Town Alexandria that day in 1987, but the Republican direct-response marketing specialist was nonetheless in a singular frame of mind. She had recently returned from a trip to Africa, where, in Dakar, Senegal, she'd visited the island of Goree, for centuries a key departure point for the African slave trade and the site of a still-standing fortress where new captives had been imprisoned.

And so it seemed eerie, Stone says, that on returning to her Virginia home to make arrangements to move her business, the first building the real estate agent offered was the notorious Alexandria "slave pen" at 1315 Duke St. "Don't show me any more," she told the agent, and immediately put a contract on the building. "It was like it was supposed to happen," says Stone, whose clients include the National Republican Senatorial Committee, the Literacy Volunteers of America and the Trump Shuttle.

A national historic landmark, this three-story building was where an estimated 5,000 to 10,000 people were kept before being shipped by the Franklin and Armfield Co. to plantations in Louisiana and Mississippi. In the decades before the Civil War, Isaac Franklin and Jon Armfield became millionaires as the largest traffickers in America's interstate slave trade. In 1861, Union troops occupied their Alexandria headquarters, turning it into a military jail.

Now the staff of Ann E.W. Stone and Associates Inc. is ensconced, working amid elegant wood furniture, oriental rugs, 19th-century artifacts and Mathew Brady photographs showing iron bars of the slave jail. Soon after taking possession, Stone began working with the Alexandria Society for the Preservation of Black Culture to dedicate the building as "Freedom House." In December 1988, Henry Bailey, a slave who passed through the pen before being sent to Texas, was honored with a plaque placed on the building's facade during a ceremony that featured Annie Bailey Rose, Bailey's 94-year-old daughter. After emancipation, Bailey traveled, reportedly on foot, back to Alexandria, where he went on to found seven black churches.

Stone is still in the process of buying the building, but says she believes that in the long run it's "not appropriate" that whites own Freedom House. "The ultimate irony would be for it to be owned by the people who were imprisoned here."