Anyone can raise a laugh at embarrassing bodily functions. James Hamilton-Paterson offers some cheerfully unrefined examples, but adds oceanography, cookery and tungsten steel tubing to the list of subjects for high-spirited humour. This is his second novel about Gerald Samper, who continues to act as disillusioned ghostwriter for inarticulate celebs, providing “cunningly crafted lies” that don’t quite become honest fiction. Samper accepts that he’s “a literary whore”, but his difficulty is in knowing where to draw the moral line. Neither his boyfriend Adrian, a glamorous marine scientist, nor his confidante Derek, a hairdresser and “complete slut”, can help him decide.

Most occupations, Samper feels, are forms of “awesome futility”. The inarticulate sports personalities he is commissioned to impersonate, their adoring fans and his unmindful readers are “all shits”, so work naturally develops into irascibility. But his rage easily overwhelms any narrow professional boundaries, and he finds it easy to denounce many other features of modern Britain, from the self-contradictory vagueness of herbal medicine to the transformation of the police from public servants into “swaggering lictors”. These rants are mostly enjoyable, their galloping misanthropy made tolerable by the rhetorical energy and comic invention with which they’re delivered.

His especial bugbear is Millie Cleat, a one-armed grandmother who has broken all records for sailing round the world and insouciantly ruined some vastly expensive deep-sea research while doing so. Millie’s “envirospiritual”denial of the science that made her success possible is provocation enough, but it gets worse when she attracts a coven of groupies who treat the ocean as a “sentient entity”. Samper sneakily persuades them that random sub-marine electronic bleepings are really conscious communication, and before long they are reverently reciting their translation: “Torrential bottoms over and torments dead tribe.” It’s a plausible example of indulgent fantasy swamping humdrum truth.

Even Samper’s pleasures can’t be taken simply. He lives in rural Tuscany (you can see the stars there, whereas in southern England the only night lights come from police helicopters and passenger jets) but it’s polluted by other Brits, “flabby folk with estuarine vowels”. He adores opera and contributes some fine pastiches of Italian hyperbole (“The Host turn to marble in your faithless mouth!”), but also deplores long-haired virtuoso pianists who provide “recurring trichological crises disguised as Bach recitals”. He relishes his own outré recipes such as Badger Wellington with Gun-Dog Pâté, but is forced instead to eat vegetarian dishes such as “deep-fried pubic hair” masquerading as seaweed.

His experiments with penile-enlargement pills have fairly unsurprising consequences. His digestive discomfiture is less predictable. Caught short in the home of a conductor he hopes to impress, he incontinently uses a lavatory that hasn’t been plumbed in, only to be pursued by an eagle-eyed toddler obsessed with talking about “poo”. Lucky Jim didn’t have it so bad. It’s even worse back in Italy. Trying to repair a neighbour’s door (though “one was made for better things” than DIY), he ends up locking himself in and peeing from an upstairs window onto the carabinieri he has inadvertently summoned. The episode unfolds as smoothly as the one with the pineapple tin in Three Men in a Boat.

Good verbal fun abounds. There is a yachtsman who dies peacefully in his sloop and a soufflé that needs a roux with a difference. Sharp-eared readers will enjoy parodies of Hardy and Housman at their gloomiest, together with sly allusions to the Book of Psalms and Traherne — Millie’s ideas are “a rich crop of orient and immortal bollocks”. Millie herself thinks that Somerset Maugham is a West Country delicacy rather like Devon cream. Passing felicities include an east European cheese that is “like spreadable leprosy” and classic Estonian poems called Erratic Boulder and The Downcast Moose.

Samper is, of course, snobbish, sexist and bigoted. He also makes you laugh and sometimes makes you think. He’s not the only person to suffer from “discontent with contentedness”, nor is he alone in wondering pessimistically whether a new baby is “merely laggard in its dying”. The book ends in undignified death and destruction. Is this still comedy or something nastier? Like the face that Millie thinks she sees on the sea bed, it all depends on the angle you’re looking from.

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