It is the spring of 1809 and a small British army is stationed in Lisbon when Marshal Soult begins the French invasion of northern Portugal. No one knows whether the British will fight or leave, but there is little choice for Lieutenant Richard Sharpe and his squad of riflemen who are sent into the beleaguered city of Oporto to rescue a British mother and daughter who have chosen to stay rather than flee southwards. But what seems like a straightforward mission becomes tangled in betrayal when Kate Savage disappears.