The great subject that's fascinated le Carre (The Night Manager, 1993, etc.) throughout his career -- what happens to the masters of tradecraft in a world that doesn't match their trade -- comes in for unsettlingly timely treatment in this latest tale of spies grown too old and knowing. Back in the sorely missed old world order, Larry Pettifer was a British double agent inside the KGB who shuttled back and forth between his two sets of masters with nary a care. Now, just as he's about to start the job his old school-friend Timothy Cranmer has found him at the University of Bath, he's gone missing, together with Cranmer's decorative lover Emma Manzini. A pair of hectoring police officers, who inevitably turn out to be Special Branch, are convinced that Cranmer knows what happened to his old colleague, and Cranmer is doubly frantic: first to hide any links between his mistress and her current lover, then to hide the fact that he may have killed Pettifer himself at their last momentous meeting. May have? It's typical of Cranmer, the good Englishman who's as dispassionate a professional as George Smiley, that he can't be sure whether or not he really killed his opposite number, a Byronic moralist full of passionate convictions about every battle he's ever fought. The news that Pettifer's old KGB controller Konstantin Checheyev has disappeared at the same time with a self-administered $37 million retirement fund allows Cranmer to identify Pettifer's latest cause -- the uprising in Checheyev's native Chechen republic -- but doesn't tell him what to do about it: He can only call on the tricks of his tradecraft one last time in a sad, mad chase over Europe and Russia to find Pettifer, without any idea what he can say if he's lucky enough to find him still alive. The debate between noncommittal Cranmer and heroically partisan Pettifer, which is at the heart of the novel, is never satisfyingly dramatized -- lots of peevish flashbacks have to do the job of pricking Cranmer's conscience -- but le Carre has never written more subtly or tellingly of the fate of agents doomed by their own success.