Tom Stoppard's career can be divided into two unequal parts. From Rosencrantz and Guildenstern are Dead in 1967 to Dirty Linen in 1976 he proved himself to be a very talented if suspiciously facile writer with an extraordinary control of the language. His plays were a constant string of puns, allusions and word play of all sorts, and if it sometimes seemed that they weren't actually about anything, their verbal pyrotechnics were delightfully self-justifying. Then, in the mid-1970s, Stoppard found his subject—the repression of individual and artistic liberty, particularly behind the Iron Curtain. In Every Good Boy Deserves Favour, Professional Foul and Night and Day he addressed his subject with fervor and eloquence, and a noticeable reduction in his characteristic reliance on word play.

With Dogg's Hamlet, Cahoot's Macbeth the two strands of Stoppard's career come together, as he brilliantly harnesses his linguistic ingenuity to his passion for...