This Christmas promises to be a distanced, unusual one. At least our expectations of family togetherness can’t be dashed in the usual episodes of arguments and hangovers, because there won’t be any family togetherness. What kind of Christmas story can match this socially dysfunctional year? We need to cast aside snowy rural idylls (Miss Read’s Village Christmas), hammy penance (A Christmas Carol) and the corpses (A Maigret Christmas) and turn to the refreshingly dysfunctional reprobates who provide the raw ingredients of Nancy Mitford’s 1932 novella Christmas Pudding.

Sixteen characters are thrown together in the Cotswolds for several farcical days over the Christmas period. As one would expect with any Christmas pudding, there are juicy bits, a dash of pure alcohol, one or two indigestible problems and a couple of nuts. Among the ingredients is Paul Fotheringay, a priggish writer who frequently wishes he were dead.

Dullness is the bourgeoisie’s most unforgivable sin

Then there is the wonderful creation of Amabelle Fortescue, the ageing doyenne of Chelsea’s demi-monde. She hires the unfortunately-named Mulberrie Farm for Christmas and invites an unappealing married couple, Walter and Sally Monteath, who freeload off everyone while neglecting their infant daughter. Nearby at the local stately home, Compton Bobbin, Lady Bobbin reigns. A riot of Wodehousian spinsterhood, she hunts foxes and hates socialists with equal passion. Her son, Sir Roderick Bobbin, enjoys his own account at Cartier and classes himself as a sexual sophisticate even though he is still an Eton schoolboy.

The farce begins when Fotheringay is forced to work undercover as a tutor at Compton Bobbin whilst accessing some family memoirs which he hopes to turn into a best-selling biography. There are marriage proposals, horse rides, social faux pas, a fake bomb and love triangles, but with Mitford the plot is not really the point. This is a viciously funny caper of the jaded jeunesse dorée coming up against the hunting classes of traditional rural England. They bob between Mulberrie Farm and Compton Bobbin enjoying rounds of bridge, cocktail soirees and suppers.

Like the perfect family Christmas, Christmas Pudding can be done with in a day

The novel’s acid humour, often of the gallows type, relies on shock. But it is dialogue where the characters come into their own and where Mitford’s genius as a comic writer is most apparent. She saves her most delicious barbs for socialists and the middle classes. Where they combine, she is ruthless. While she can forgive their dirtiness — these men in grey flannel trousers or those “dirty young women with long greasy hair” — Mitford will not forgive them their dreariness. Dullness is the bourgeoisie’s most unforgivable, non-U sin.

While Mulberrie Farm barely has an inglenook fireplace in need of a sweep, the upper classes haven’t got the first idea how to look after their stately homes. Their inhabitants wire up Venetian chandeliers into electric ugliness, are careless and dismissive with the Waterford crystal and are such philistines that the best paintings are shoved into the maids’ corridor.

Lady Bobbin goes in for an orgy of Christmassing. The house explodes into a confusion of German trees, Scottish fabrics and choral medleys. An awful procession of duchesses and dogs arrives, bursting out of Rolls-Royces and train carriages. Lord and Lady Mackintosh are caricatures of Scottish aristocracy, all tartan stockings, kilts and bowls of porridge, eaten eating standing up. A titled relative, a Conservative MP, is “a monster of denseness and stupidity”.

The upper-class fear of revolution provides many jokes. Lady Bobbin believes the foot and mouth disease which has halted the hunting season is a Bolshevik plot designed to unseat her; the Tory MP misinterprets a joke as an attempt on his life by revolutionaries and summons the police. Everyone under 30 yearns to be as far away from deepest Gloucestershire as is humanly possible, doing something jolly back in London.

Christmas Pudding was Mitford’s first published work, 13 years before her triumph The Pursuit of Love, but you can see her flexing her muscles, particularly in the finale where love conflicts, the sex question and marriage crop up. But like the perfect family Christmas, Christmas Pudding can be done with in a day. Best devoured swiftly with a stiff drink, and in a cosy armchair as far away from your family as possible, it is the tonic Christmas 2020 is crying out for.