This is not about Blair - honest

YOU have to hand it to Robert Harris: he is our foremost literary guide to the freefloating anxieties of an era.

Germany reunifies and he produces Fatherland, set in a world run by the Nazis. Post-communist Russia unleashes itself after the fall of the Soviet Union and there he is with the chilling Archangel, about a Russia in the grip of Stalin's reincarnation.

After a break from the thrills and spills of 20th-century history with the Compromised by is not toga-saga Imperium, he's back in the urgent, anxious present with The Ghost. Guess which troubled empire is at the root of it this time? Bush's America, not wholly unexpectedly, and the role of the British Prime Minister, whose closeness to the heart of darkness is his nemesis.

Harris has coquettishly denied that this is a roman-à-clef about Tony Blair's relationship with George Bush.

Some roman, some clef. From the first page, it is a cheeky and forthright set of Blair-studies, interlaced with the author's own moral queasiness at the unpalatable outgrowths of the war on terror CIA ghost flights, renditions and the tacit support for the less accountable methods of counter-terrorism.

All the suppressed enmities, resentments and jealousies of a political team in exile are there, too. The relationship of Adam Lang, the ex-PM with his wife and his chippy and seductive female aide doubling as mistress, is as icy a ménage à trois as ever depicted on the page.

Not that Lang gets much time for mistressing as he toils on his memoirs, but not fast enough for Mrs Lang, who is fed up with life at the behest of a rampantly commercial publishing company: "Rhinehart Publishing UK consisted of five ancient firms acquired in a vigorous bout of corporate kleptomania & upsized, downsized, rebranded, renamed reorganised, modernised, merged and money Blair - finally dumped in Hounslow." You can tell Harris is a best-seller no one else would dare evoke modern publishing with such savage accuracy.

As a former ghost myself on a bigbucks project, I thought Harris captured the uneasy intimacy of this relationship beautifully. The co-writer has to ask the questions the star wants to duck: "Did you sleep with her? Approve his abduction? Make a major error of judgment? Lie?" Both of you are subject to the bigger force of Mammon which wants only one thing the book big, bold and on time.

The main flaw in the novel is predictability. From the moment the previous ghost-incumbent is found at the bottom of the Atlantic we can guess - honest which political waters we are in. Large US military-industrial companies with tentacles in academia? British leaders who back US foreign policy? Must be some dark reason for that.

Harris gets the tenor of the times all right. What would once have been seen as the conspiracy theories of the wilder Left shores is today mainstream.

Who doesn't disapprove of dodgy renditions of terror suspects? But who does not then blame governments when terrorists get through the net and blow us up and did America really start it all? These banality traps loom and Harris attempts to offset them. So the Guardian-reading girlfriend gets the odd pasting: "Given a choice between an evening of her smug Left-wing moralising and the prospect of working with a so-called war criminal, I preferred the war criminal" and the Robin Cook character, combining comically high purpose and low motives, is nicely dissected "as hell-bent on revenge as any former lover". The saving strength is that he really understands politicians and their psychology, from the tiredness and frustration that always hangs around former leaders to the desire for vindication.

Harris turned his book around in record time and it is finely calibrated for the melancholy, resentful mood of the post-Blair era. Much to enjoy there then unless you're Tony and Cherie.