Tonight on Amanpour and Company: Randall Kennedy, Law Professor, Harvard University; Olympian Michael Phelps, gymnast Aly Raisman, tennis champion Serena Williams, and soccer icon Megan Rapinoe; Ahmad Sarmast, Founder/Director, Afghanistan National Institute of Music and Afghan Youth Orchestra members Zohra Ahmadi and Ali Sina Hotak. Walter Isaacson interviews Raj M. Shah and Christopher Kirchhoff, Co-authors, Unit X.