Tonight, Bill Clegg, author of the new memoir Ninety Days, a sequel to his Portrait of an Addict as a Young Man, which one reviewer described as "a stylish record of his swan dive to rock bottom," joins us Upstairs at the Square with Rachael Yamagata -- join us to find out why she's only the second guest to be invited back in six years -- and host Katherine Lanpher for an evening of performance and discussion at the Union Square Barnes & Noble. Showtime is 7pm sharp, and it's free.