up next, theatre historian thomas bogar revisits that night through official testimony of some of the actors and employees of the ford brothers. this event was hosted by the national archives and lasts about an hour. >> it's funny when you start out to work on a book about something so well known in american history, such a signal event, you have to really aim for who you think your readers are going to be. i started to find early that there's such a spectrum. on one end you have people who are real scholars of the lincoln assassination, who are familiar with the most arcane details. and then you have on the other end what was exemplified by my visit recently to a city that will remain nameless. when i was doing research on the book, i was having dinner in that city in a fine upscale restaurant. and the manager of the restaurant, a young woman in her 30s, came by and said -- asked me what brought me to the city. when i explained that i was doing research about the lincoln assassination she looked at me blankly for a minute and then said, "lincoln was assassinated?" so i have to aim so