For months the Fox advertised the appearance of Cherry Jones in Doubt, John Patrick Shanley's much-honored parable about suspicious goings-on in a Catholic school in the Bronx. It's always exciting to see an acclaimed actor in his or her Tony Award-winning performance. As opening night neared, the drumbeat grew ever louder: Cherry Jones! CHERRY JONES!! So you can imagine the disappointment of arriving on opening night and encountering that dreaded lobby sign: AT THIS PERFORMANCE... Vocal problems had forced Jones out; for the very first time, the role was to be performed by the understudy, who received a whopping 90 minutes' advance notice in which to prepare for her debut. But who was that understudy? None other than Darrie Lawrence, familiar to St. Louis audiences for her many roles at the Rep. She was a brilliant Sister Aloysius. At the emotional curtain call, when the other actors joined the audience in applauding Lawrence's grand accomplishment, her beaming smile broke through Sister's perennial frown and filled the Fox. Everyone there that night was reminded of why we keep returning to the theater: for those rare, unexpected experiences when something live transmutes to something precious and memorable.