After a secret drone strike on a civilian target in South Sudan, RAF air marshal George Bartholomew discovers that a piece of shrapnel traceable back to a British Reaper has been left behind at the scene. He will do anything to get it back, but he is not the only one. Dissatisfied with his life and ousted from the marital bed, Associate Professor Gabriel Cockburn, an ambitious botanist at Bristol University, sets out to South Sudan in pursuit of a rare plant that is crucial to his research. Once there, he finds himself caught up in the travails of a young Sudanese woman, Alek, who agrees to guide him through dangerous territory to find the plant. But Alek has an agenda of her own.