Brazzaville Charms, by Cassie Knight

The Congo syndrome is the curse of going unnoticed in an indifferent world. It is the reason why the West Africans of The Gambia have preserved the colonial-sounding definite article in their country's name, as a service to postal workers apt to send their letters to Zambia. In between the two lies the Republic of Congo, sometimes known as Congo-Brazzaville, populated by only three million people and not to be confused with the adjacent, huge Democratic Republic of Congo. Cassie Knight spent four years in the smaller of the two states, mainly working for the Catholic relief agency Caritas.

Since the former French colony's first offshore rig began spewing oil in 1972, Congo has grown into Africa's fifth producer of crude and the continent's most indebted country. Its path to mass poverty has been paved with civil wars, corruption, French interference and ethnic tension.

Knight's country synopsis in this book about "magic and rebellion in the Republic of Congo" is thorough and modern. By paying a visit to the King of the Bateke – who claims that his predecessor was duped by the French in 1880 – she also avoids the pitfall of telling African history purely from a European perspective.

Two-thirds of the way through, Knight's journalistic rigour erupts into evocative writing. We realise what really fascinates this anthropology graduate: witchcraft, secret societies, religious exorcism and sorcery. Congo – where untamed nature remains in cahoots with the supernatural – is a society built on fear. Here, jealousy conspires with the spirits to wreck lives, sicken people and provide an excuse for resignation to your lot.

Atonement can only be won through sacrifice, and sometimes not at all. A man saw a vehicle driving through a thunderstorm with its aerial up: "Be careful! You will be struck by lightning," he warned the driver. When the vehicle had an accident, the man was blamed and hounded from his home.

Knight rightly criticises Western countries for turning a blind eye to abuses in Africa as long as the oil keeps flowing. She believes that the failure of Congo is caused by the cohabitation of greedy politicians with superstitious subjects. And she gives us all the elements to conclude – although she doesn't herself – that Africans urgently need to stand up to the spirits. Otherwise, they will continue to be ripped off by politicians who have a pragmatic understanding of the fastest way to fill their bank accounts.

Frances Lincoln, £14.99.Order for £13.49 (free p&p) on 0870 079 8897