“By the time I was led to the set for my big scene, I had reached a pitch of anxiety that I had never experienced, and hope never to again. Rather than appear before the cameras, I would have gladly faced a firing squad. Or worse, a ravening mob made up of every actor, author or director I had ever panned... It’s not that I couldn’t infuse the line with enough emotive substance to please a Stanislavski. No, I’m afraid the words I had been relentlessly drilling for the past 24 hours--to the cat, to the refrigerator, to empty elevators and to the brisk air of Madison Square Park--wouldn’t come at all.”
-- NYTimes theater critic Charles Isherwood makes a cameo appearance in Gossip Girl, and survives to tell the tale.
P.S. Who's Addison DeWitt? Here, here and here.