As a former assistant to David Letterman, Stephanie Birkitt had been the subject of national attention before. The 34-year-old New Hampshire native taped more than 200 segments for The Late Show from 1996 to 2008 including interviews with Survivor castoffs and reports from the Winter Olympics. But when Letterman announced on his show on Oct. 1 that he'd been the victim of an $2 million extortion attempt, Birkitt found herself in a different and much less flattering spotlight. According to Letterman, Birkitt's ex-boyfriend, a CBS News producer named Robert (Joe) Halderman, tried to blackmail him by writing a screenplay, based partly on a diary of Birkitt's, about the wealthy and now married talk-show host's habit of seducing female staffers. Since the alleged plot was revealed, Halderman has pleaded not guilty he claims it was an aggressive business deal gone awry and the media have yet to hear a peep out of Birkitt, who may be trying to stay out of the limelight for good.