rkas, what is this? mark: it grew out of a series on television about first ladies. we have taken every single program, we had some of the greatest historians on the presidency and first ladies, and put them into narrative form in each chapter. every first lady has a chapter, in which we learn their biography, that includes their time as first lady. some of them had great influence, some of them had less of an in humans. >> was it hard to find records on first ladies? some first ladies -- isk: some first ladies, it easy. abigail adams has thousands of letters where she is lottery -- lobbying john adams to remember the ladies. --tha washington has all of has only two letters that exist. the further along you make it in time, you see the adaptation of technology and the role of first lady begins to emerge. now, we have a very public role for the first lady. in the past, they could get away if they wanted to be behind the scenes. you can't do that anymore. >> former first ladies running for president. mark: the chapter on hillary clinton, for anyone who wants to know ho