A missionary in Africa who provides Nathan Price and his family with supplies, shelter, and advice about how to get by in the Congo. Underdown is a useful expository device in the novel: whenever there’s a big historical event in the Congo, we can count on Frank Underdown showing up to explain it to the Prices—and, by extension, to us as readers. At the same time, the Underdown and his family serve as examples of the corruption and failure of missionary activities in the Congo, living in a mansion with servants rather than living among the people they have come, ostensibly, to serve. After the military coup that leaves the Congo in the hands of Joseph Mobutu, it is Underdown who advises Nathan to leave the country immediately. Nathan stubbornly decides to stay behind, ending his already strained relationship with Underdown.