Thorne-Smith was sitting right there! And she loved every minute of it, she told Vanity Fair Tuesday. If you’ve never seen the segment, I won’t spoil it for you, beyond the moment O’Brien asked what the film would be called, and Macdonald piped up: “If it’s got Carrot Top in it, do you know what a good name for it would be? Box Office Poison.” And on this night he was in top form, heckling the absent Carrot Top and the film Thorne-Smith was gamely trying to promote. If he was on with O’Brien, you were staying up to watch.

Macdonald was to Late Night With Conan what Don Rickles was to Johnny Carson’s Tonight Show, Steve Martin to Late Night With David Letterman, and Martin Short to everybody.