Spain, Summer 1813
After a campaign battle, Sharpe discovers that a group of soldiers led by Sgt. Rodd are deserting. The provosts arrive too late to catch them, but arrest one of Sharpe's men for stealing a chicken.
A relative of Wellington's arrives in camp, Mrs Bess Nugent and her daughter, Ellie, trying to find Mr Nugent who has become lost in Spain while searching for a hoard of Aztec gold, supposed to be buried in the hills. Wellington refuses to mount a search and orders the women home.
Wellington is short of men, and agrees to exchange 52 British deserters, captured by the Spanish partisan El Casco, for Baker rifles. Sharpe is ordered to manage the exchange. On the journey, Sharpe and his men realise they are being followed. It is Bess and Ellie Nugent. The exchange takes place. One of the deserters is smoking Nugent's pipe. Unable to persuade Sharpe to continue the search, Bess and Ellie go alone. Sharpe cannot stop them, so he sends the provosts back with the deserters and he and his men go after Bess and Ellie.
Bess and Ellie are ambushed by guerrillas, Bess is killed and Ellie is carried off into the mountains. Whilst in captivity, she sees her father who is also a prisoner, but he has lost his mind. Sharpe is left with no choice but to mount a rescue in the caves where Ellie and her father are held.