In the bitter winter of 1809, the French are winning the war in Spain. Britain's forces are retreating, being hotly pursued by Napoleon's troops. Lieutenant Richard Sharpe and his detachment of riflemen, have been cut off, and are being pursued by an Irishman called Patrick Harper. Sharpe finds an ally in a Spanish cavalry officer, Blas Vivar, and companionship in an English refugee, Louisa Parker.