Stephen Sondheim at 80

Shooters
First staged off-Broadway in 1991, Assassins explores the lives of the men and women who have attempted to kill U.S. Presidents. The highly unusual (for a musical) theme disturbed many critics, but thrilled others. Writing in the New York Times, David Richards said, "No musical in the last decade has ever dared this much. It turns the musical's traditional values inside out and delivers a rebuke to George M. Cohan on his very own turf."

• Glee's Broadway Roots