Kristine Kupka was 28 and five months pregnant when she disappeared from her Brooklyn home on October 24, 1998. A Baruch College honors student and philosophy major planning to attend law school, Kristine left that day after telling her sister she was going with her former chemistry instructor Darshanand Rudy Persaud to see an apartment he said he was renting for her. She left without a coat or many personal belongings and was never heard from again.

Persaud, the last person known to have seen Kristine, told police he drove her to a shopping mall, waited while she shopped, then dropped her a couple of blocks from her home; he could not name the mall. Authorities say he had a clear motive but investigators lacked physical evidence to link him to the disappearance. A 2010 tip prompted a dig in the basement of a Queens shop once owned by a relative of Persaud’s, but nothing was found.

Kristine’s family describe her as strong-willed, intelligent, and excited to become a mother; her sister Kathy has worked to keep the case active. Does anyone have information about Kristine’s movements on October 24, 1998, or recall seeing her that day?