The Three Musketeers by Alexandre Dumas, trs Richard Pevear

Drugs? Incest? Not in front of the children

Alexandre Dumas is an interesting case. His best novels have been in print since they were first published. The Three Musketeers and The Count of Monte Cristo are also among the literary works most frequently adapted for the screen. Yet Dumas's literary reputation is shaky. In France, standard histories of literature have more or less ignored him: the tone was set by Gustave Lanson (1895), who dismissed his fiction in a sentence. Dumas, he said, "took hold" of the historical novel and "diverted it outside literature and outside art, for the amusement of the masses".

In fact, Dumas's popularity has been held against him; but that is not the full story. As the 19th century advanced, Dumas came less and less to fit the image of the literary creator, dedicated to his art and to the search for the mot juste. He was paid by the word and produced millions of them, in the form of novels, plays, short stories, journalism, travel writing, memoirs, historical works and even cookery books. Worst of all, he used collaborators, so you can't be sure how much of The Three Musketeers was written by Dumas himself and how much by his favourite assistant, Auguste Maquet. The influential British critic George Saintsbury summed up the charges against Dumas in his history of the French novel (1919): immorality (more of that later); plagiarism and collaboration; and being "a mere pastimer" with no literary quality.

None of this affected Dumas's sales (especially not the charge of immorality), but it did influence the way his books were perceived. He was classified as a writer of swashbuckling adventure stories. He could not quite be seen as a children's writer - after all, the hero of The Three Musketeers sleeps with the villainous Milady, as well as with her maid, while pursuing another, married woman, which is not the kind of thing you get from the heroes of G A Henty or John Buchan (it was Alfred Hitchcock, remember, who handcuffed Richard Hannay to a woman in The Thirty-Nine Steps). But, despite writing novels which involve incest (La Reine Margot), lesbianism, hallucinatory drugs (Monte Cristo), adultery, sadism and lots more, Dumas was seldom considered entirely a grown-up writer, either; and these perceptions were shared by his 19th-century translators.

As Richard Pevear remarks in his preface to this new version, Victorian translators would remove "all of the explicit and many of the implicit references to sexuality and the human body", with the result that certain scenes become "strangely vague". Even translations of the 1890s, which are more daring than earlier ones, exhibit some peculiar inhibitions. For example, in the scene in The Three Musketeers, where d'Artagnan is surprised after seducing Milady, Dumas writes (and Pevear translates), that she "with one bound threw herself half-naked" at him. The 1895 translator refused to let his readers imagine this half-naked woman, deciding rather to make d'Artagnan "half-naked on the bed": after all, a half-naked man can still be decently covered, while a woman cannot.

The definition of Dumas as a writer of mere adventures became self-fulfilling for these 19th-century translators, because they would cut huge chunks that, in their opinion, held up the narrative. This is not so important in the case of The Three Musketeers, but it makes a different book out of The Black Tulip, where Dumas make much of Dutch culture and history. And, apart from bowdlerisation and cuts, the Victorian translators made heavy work of Dumas's language, losing much of his humour in verbiage: eyes looking at an unexpected feast don't pop, they "dilate in such a manner that they seem ready to burst"; and so on, with a good smattering of "zounds!", "faith!" and other exclamations.

If you want to know why this is a shame, read Dumas's work in modern translation. Start by taking a fresh look at The Three Musketeers. The son of a general in the revolutionary army, Dumas was only 13 when Napoleon was defeated at Waterloo: he spent his youth under the dreary Bourbon restoration and belonged to a generation whose young men felt they had missed out on the excitement of revolution and empire. This is why he especially loved the 17th century, the period of this novel and its sequels, seeing it as a lost age of freedom, passion and adventure. It is Dumas's own evident enjoyment, not crowd-pleasing effects, that explains the enduring popularity of his work. Richard Pevear has produced a Three Musketeers for our time, currently available in this handsome hardback edition.