The Scandal of the Season, by Sophie Gee

In 1711, Alexander Pope was an earnest young poet, admired by critics but yet to produce the bestseller that would make his name. He had several projects in mind: perhaps a translation of Homer, or a Miltonian epic on the theme of earthly paradise. His publisher agreed that this was very fine, but urged him to try a scandalous satire instead, perhaps featuring recognisable people from high society – the sort of thing his contemporaries Swift and Steele often dashed off.

That's not really my style, said Pope. But that year an incident occurred among his friends which caught his fancy. An aristocrat humiliated a young woman with whom he had been having an affair by slicing off a lock of her hair at a party – a startling assault, which publicised the intimate relationship between them and destroyed her reputation.

Pope made the incident the basis for "The Rape of The Lock", a satire so successful that it set him up for life. Now Sophie Gee reverses Pope's alchemy, and converts the story back from poem to source. The characters resume their original names, the sexual and political background is unfolded, and all is re-staged in a novel that is a joy throughout.

Gee's great strength is her command of the language. A literary historian, she pitches her 18th-century dialogue just right, avoiding both anachronism and archaism. Her confidence frees her characters to act naturally, so that we instinctively respond even when (as historical characters should) they behave in ways unfamiliar to us.

The most fascinatingly alien thing about them is their liking for elaborate games of wit. Being amusing on demand was an essential skill for men and women alike. If your hostess swatted a quip at you over the dinner table, you had better volley it back with added spin – and be prepared for it to come back again and again. The heroine's social downfall occurs partly because she fails to produce a devastating riposte after her lover's attack. With everyone staring at her, she flaps her mouth mutely and faints. Understandable, but a mistake. The last word goes to Pope, the cleverest of them all.

Some of Gee's best lines are actually his, but she devises the rest of the dialogue with panache. The ping-pong of repartee is one of the book's delights. The historical scenery is good too, always interwoven with characterisation and plot. Gee does not tell us how potholed the streets are, or how cold and uncomfortable the carriages; she shows us three ladies riding in a cramped coach, an inadequate fur blanket over their knees, being flung about as the wheels plunge in and out of the ruts.

And nothing could evoke the 18th-century diet more memorably than the following conversation between a couple planning a dinner. "For the first course a fillet of veal," says the wife, "a fricassee of lamb, a dish of peas and a sallet of herbs. Then we shall have beefsteaks and a game pie, with asparagus." The husband cuts in. "My dear," he says, "I do not think that the company will be expecting peas as well as asparagus. They will think it indigestible." This is historical fiction at its wittiest and most enlightening.

Sarah Bakewell's latest book is 'The English Dane' (Vintage)

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