[1] The novel was republished in 1997 for United States readers as No Mercy: A Journey to the Heart of the Congo.

Written in diary form, and set mostly in the People's Republic of the Congo, the book begins as a search for Mokèlé-mbèmbé, a legendary dinosaur of the area.

In addition, the book also provides an expose of the Bantu and Pygmy peoples, including their lives, spiritual customs and beliefs.

[2] The book also discussed problems these people face, such as the Yaws disease.

O’Hanlon's adventure, he says, is by turns dangerous and funny, as he "takes the long way to the lake and nearly gets killed by a village headman", trying to save a baby gorilla, while he "battles his demons and the haunting spirits of Central Africa."