Why would a “born-again atheist” sponsor a place of pilgrimage where Princess Diana is rumoured to appear? Well, because it's the kind of thing the writer Gerry Samper does. In the third volume of his consistently enjoyable memoirs the pseudo-shrine is only one feature of a plot in which he negotiates with corrupt Italian politicians and obstructive Vatican officials for an “exit visa out of the land of servitude”. His former neighbour and bothersome friend, the Voynovian composer Marta Prskjl, is implicated, too, collaborating in an opera on the royal martyr. Many outrageous things happen, most of them funny.

It's not all as sharp as it might be. Words such as harpy and harridan are asked to do more than they should, and Gerry's sort-of lover Adrian is allowed to write lengthy e-mails in which, after humdrum discussions of the politics of oceanography, he becomes almost sentimental. Usually, however, the tone is bracing. The topics may be unoriginal but the inventive and unforgiving irascibility with which they're pursued keeps our minds alert and amused. And Gerry doesn't get all the best lines. His friend Joan memorably describes an estate agent as looking “like a ferret that's been through a car wash”.

For all its scenes of fantastic farce, this is not a world such as Blandings into which we can escape. Aesthetic sensibilities “are constantly being outraged” and “it is never safe to heave a sigh of relief”. Nor is consolation to be found in religion. Although a priest claims that “doubts are to Christians what erections are to adolescents”, Gerry finds life enduringly bleak. The night thought occurs that we are “plankton adrift in an ocean of time”. One can only be amused “if one is a total pessimist and misanthrope”.

In Britain, Gerry finds himself “adrift between envy and repulsion”, and makes a strong case for his feelings. Grinning television presenters preside over news broadcasts offering “a loony chaos of dizzying junk masquerading as information”. A star reporter has “an expression of mulish equanimity like that of a garden gnome used to being lied to”. A hostile journalist thinks Les Fleurs du Mal is a new cologne by Stella McCartney. Garden centres (“the new cathedrals of the secular age”) sell scented candles called Beingness. Gerry's disgust at all of this is contagious and convincing. His love of strange recipes, wordplay and solitary singing - he thinks of himself as Robinson Caruso - is as strong as ever. Rodent fillings in his customised vole-au-vent trigger a “major barf-fest” when a fieldmouse turns out to have been poisoned and elicits a “sudden hawser of blue-brown vomit”. A scheme for dealing with the population explosion by eating environmentalists suggests, “Eat up your Greens!” as a nursery injunction. Scurrilous celebrity variants on peach melba include Stewed Ham O'Toole and Thai Chicken Gary Glitter. Anagrammatically, Lyme Regis becomes Grey Slime, Reader's Digest turns into Dead Registers, and Princess Diana re-emerges in the novel's title.

Her theatrical canonisation occupies the book's final section. James Hamilton-Paterson has the rare gift of describing nonexistent music so that you can hear it in your head. Gerry's libretto involves devices “novel in opera although not in gynaecology”, and adds to the themes of marital breakdown and shopping such sombre moments as a beggar girl singing, “There's not much Versace/here in Karachi.” Marta's score - once “the Di is cast” - includes a rhythmically menacing chorus for paparazzi, set as Berg-like Sprechgesang, while the orchestral bass line quotes a fugal motif from the St Matthew Passion. As with most of the book, if that's not real, it surely deserves to be.

Rancid Pansies by James Hamilton-Paterson
Faber £12.99 pp272

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