On Brazzaville Beach, on the edge of Africa, Hope Clearwater ponders the strange circumstances that led her to leave her husband John, and his mathematical obsessions, in England and venture to Africa to help world-renowned scientist Eugene Mallabar with his studies of wild chimps. But the more Hope studies Mallabar, the more she comes to believe that something isn't right. That behind Mallabar, and his obsessive work, there lies another, more sinister truth: one that might also help explain Hope's reasons for leaving England . . .