The latest incarnation of Conrad's Congo

The nightmare journey evoked in Heart of Darkness inspired the film Apocalypse Now and has now been adapted as a graphic novel.

Could the Polish-British novelist Joseph Conrad ever, in his wildest dreams, have imagined that his most famous work, Heart of Darkness, would one day be made into a graphic novel? Unlikely. And yet such is the latest incarnation of his 1902 colonial fable, as interpreted by the Kenyan-Swedish artist Catherine Anyango with text adapted by David Zane Mairowitz. The result, according to early reviews, is a triumph; "quite magnificent" according to Rachel Cooke in The Observer, "every page is extraordinary, and extraordinarily beautiful".

In keeping with the novella's over-arching theme of darkness - that of the Congo, where the story is set, that of the colonial ruler's treatment of the local people, and that of human nature in general - the images are set in monochrome. "I wanted to draw the reader in with seductive imagery, and then show them that even in the most beautiful setting, terrible things can happen," said the artist in a recent interview with the Guardian.

Cleverly, the text has been interlaced with excerpts from The Congo Diary, Conrad's own personal account of the time he spent on a voyage similar to his protagonist Charles Marlow up the Congo River in 1890. Some of the events and characters in Heart of Darkness were based on Conrad's real-life experiences, according to King Leopold's Ghost, the historian Adam Hochschild's best-selling 1998 account of the then king of Belgium's exploitative rule over the Congo Free State.

Anyango, who grew up in Kenya, used individual accounts of the barbarism inflicted on the Congolese people to inform her visual style. In one instance, it was a photograph of a man from a village in the Upper Congo contemplating the hand and foot of his daughter. They had been cut off and sent to him by guards after the Anglo Belgian India Rubber Company ordered them to attack his village for failing to supply the company with enough rubber. "I put him on one page, and similar portraits on others, so the Congolese characters have resonance at least for me," Anyango told the Guardian, "even if they remain stereotyped because of the existing narrative".

In doing so, the artist has, according to Cooke, "brought to life Conrad's nightmare journey far more successfully than the movie-makers who came before her." Most famous of those is Francis Ford Coppola, whose loose 1979 screen adaptation of Heart of Darkness,Apocalypse Now, has become a classic in its own right. In it, Coppola transplants the action to Vietnam, where Captain Willard (Martin Sheen) is sent upriver into the dense Cambodian jungle to find Colonel Kurtz (Marlon Brando) and kill him because he is reported to have gone insane. As he lies dying, Kurtz recites an excerpt from TS Eliot's 1925 poem, The Hollow Men, in homage to the poet, who used a line from Heart of Darkness - "Mistah Kurtz - he dead" - in its epigraph.

Though Heart of Darkness was intended as an exposé of the truth behind the myth of colonialism, it has been criticised, most famously by the Nigerian writer Chinua Achebe, for its racist and dehumanising treatment of the Congolese people. They were, he said in a 1975 lecture on the subject, reduced in the book to merely an extension of the jungle, with no apparent language or culture of their own.

Conrad's grim subject matter seems an unlikely choice for adaptation to a traditionally light-hearted medium such as the graphic novel. And yet, increasingly, it seems, great works of literature are being reinvented as such. In 2007, the cartoonist Robert Crumb, together with David Zane Mairowitz, published Kafka, a monochrome graphic representation of the writer's life as well as the plots of many of his works. Likewise, Tamara Drew, the new film written by Stephen Frears about a young newspaper columnist who causes controversy in a rural writer's retreat, was based on a cartoon strip by Posy Simmonds, which appeared in the Guardian. Simmonds was in turn inspired by Thomas Hardy's 1874 novel, Far From the Madding Crowd.