Paul Theroux has chosen to measure himself against a very tall ghost indeed: Joseph Conrad. Jungle Lovers is an audacious attempt to tell the other half of The Heart of Darkness, to reveal precisely what it was about Africa that drove the humanitarian trader, Kurtz, out of his mind and reduced him to a raving savage with human skulls impaled atop his palisade.

The novel's setting is the Central African peanut republic of Malawi, a country that is in actual fact at least half fictitious—one of those arbitrary creations of European colonialism that bears little relation to any economic, geographical, ethnic, or other observable reality. It is a figment of the imperial imagination that has been converted, by the stroke of a pen and the hoisting of a flag, into a modern political illusion. The place is ideal for Theroux's purposes; he could scarcely have invented a...