Lady Montdore, the manipulative presence who hovers over Nancy Mitford’s Love in a Cold Climate, is not so much unempathetic as anti-empathetic. Of an unattractive young woman whom she learns is training to become a vet, she remarks, in a rare moment of approval: “No point in cluttering up the ballrooms with girls who look like that, it’s simply not fair on anybody.” Nor is others’ misery likely to make much of an impression on her. “I love being so dry in here,” as she says while she’s being chauffeured to her stately home during a rainstorm, “and seeing all those poor people so wet”. It’s not that she’s a sensualist – at least not when the novel opens – but that no pleasure can be truly satisfying unless it is firmly located in a pecking order. What’s the point of dry for dry’s sake?

The social hierarchy that most preoccupies her is the one that she hopes her only child Polly (full name: Leopoldina) will top when she marries, a manoeuvre with which Lady Montdore is all too familiar, having begun life as Sonia Perrotte and wed her way out of the fate that might otherwise meet the daughter of a penniless country squire. She has certainly taken her social ascent seriously, devoting her life to keeping those beneath her in their place with “the charm of a purring puma”, working her servants to the brink of exhaustion to provide the fabulous comfort and entertainment on offer at Hampton, her country house, and developing an unbreachable carapace in the face of others’ disapproval. Her “rampant vulgarity” is legendary, and her “worldly greed and snobbishness, her terrible relentless rudeness, had become proverbial”; so disliked is she that people assume her origins might even be – the horror! – transatlantic.

But the best baddies have a little something that makes us bend towards them, despite our better judgment. As Fanny, the novel’s narrator and Mitford’s alter ego notes, “it only required an occasional hint of mutual understanding, a smile, a movement of sympathy to make me think I really loved her”. Partly, it’s Lady Montdore’s fabulous self-delusion: cocooned in wealth and comfort with little to do but arrange balls and paint pictures with the egregiously awful Boy Dougdale, she thinks of herself as a thorough grafter. “I like to work hard all day, she says, “and then have agreeable company and perhaps a game of cards in the evening”. It’s also the fact that she often takes the flak for her near-universally adored husband: “Lady Montdore was for ever doing common things and mean and she was intensely unpopular, quite as much disliked as her husband was loved, so that anything he might do that was considered not quite worthy of him, or which did not quite fit in with his reputation, was immediately laid at her door”. To the very occasional naysayer, Lord Montdore appears to be “a wonderful old fraud”.

We might even feel a jot of sympathy with her when Polly, far from making a suitable match, runs off with Boy, her uncle by marriage, many years her senior, rumoured to be Lady Montdore’s lover and certainly just as snobbish as she is. Gone in a flash are Sonia Perrotte’s dreams of seeing her daughter married into royalty. No wonder she tells the “incestuous little trollop” she never wants to see her again.

All she and Lord Montdore can do is turn to a distant relative, Cedric, destined to inherit “all this”, who arrives in a flash of glamour and sets about transforming life at staid old Hampton. Lady Montdore’s rebirth is a masterpiece of dramatic irony: just as we see her enjoying the wardrobe makeovers, slimming massages and Venetian balls she is called on to mount (and fund), we see Cedric getting her exactly where he wants her. Not that you’d want to waste too much time feeling sorry for her.