["Night and Day"] surprises us by not surprising us. For the first time in his career, [Tom Stoppard] has written a conventionally straightforward melodrama, showing few traces of the breathtaking verbal acrobatics at the top of the tent of language with which he has previously dazzled us. There is much talk in the play, and it proves to be Shavian in a bad sense, which is to say that it is more garrulous than witty. A pertinent topic for discussion has been chosen by Teacher Tom: What does our newspaper press exist for, except to make money? If it can be argued to have a purpose beyond mere money-making, is it one for which the lives of individuals—and, indeed, of entire countries—ought to be sacrificed? Mr. Stoppard was a journalist before he was a playwright, and he can make a strong case for the power of...