Perhaps it seems captious to comment that a book which is described as a ""spy thriller,"" a ""philosophical novel,"" as ""comic"" and ""sometimes hilarious,"" but written with ""suspense and serious purpose"" as well as ""originality and witty grace"" challenges the reviewer to find some other attributes to apply. With the exception of ""hilarious,"" most of these disparate, conglomerate qualities are present in Dame Rebecca's novel (her first in ten years) which not surprisingly is concerned with the meaning of treason while dealing with an authentic incident involving treason which has been fictionally paraphrased here. This is perhaps the most fallible part of the novel, this transition between the documentation and the drama, and the famous conversation on a train (the authentic episode) sometimes slows the wheels of the story itself. Aboard it, going back to Tsarist Russia, is Nikolai Nikolaievitch and his granddaughter, Laura, eighteen; Nikolai, by far the strongest character in the book, an imperious idealist, remembering, ruminating, rumbling, is warned at this point that he has been spied upon within his house by his presumably faithful if unctuous attendant, Kamensky. Kamensky is, according to Chubinov, the shabby informant, also a terrorist spy, a double agent whom young Laura has already had reasons to distrust. Nikolai's death, as a result of this revelation, and the further violence to which it leads, is all only a personalized demonstration of Hegel's theory of the dialectic--that antithesis will destroy thesis and something better, synthesis, will result. In this case the divisiveness of Tsarist vs. terrorist Russia hopefully made possible the emergence of a more enlightened regime.... Dame Rebecca's story is told in an unhurried, modulated fashion with an elegant descriptive sense; her perfectly poised sense of time and place extends like a canopy over the turn of the century where old, firm, proud convictions were displaced by insurgent thoughts and actions. Always an admirable writer, her incandescent style lights up the pages.