At her best, Jilly Cooper has a genius for combining soft-focus romance with the beady, pitiless social comedy of Jane Austen, or at least Nancy Mitford. What's more, vintage Cooper Riders, Rivals, those slender 1970s love stories Harriet and Imogen displayed a gimlet eye for what Henry James described as "solidity of specification". The food was delicious, the clothes covetable (I distinctly remember a tight linen dress the colour of a New York taxi), even the perfumes were precisely matched to character (Fracas for the bitches, L'Eau d'Issey for the eco-types). Unlike the permatanned fantasies of her contemporary Jackie Collins, Cooper's world was earthy, the urban glamour literally grounded by a muddy shire Tory circuit of hunt balls and point-to-points.
In recent years, she's succumbed to the lure of melodrama, and her books have become correspondingly more overblown and baggier. Score! featured a serial killer, while the last, Wicked, was inhabited by a cast of feral teenagers (one of whom was helpfully called Feral) whose working-class patois never quite rang true. Fortunately, Jump! is in terms of scenery at least a return to form. The story of a widow who saves an injured horse, it's immersed in National Hunt racing, a world as heterogeneous as Harris tweed.