It's 1811.

 Wellington has finally driven Napoleon's armies from Portugal, but the cost has been high. Fearing a French counter-attack, the British must rally their tired men and go on the offensive.

 Lieutenant Hamish Williams of the 106th Foot relishes the call to action. Spurred on by the prospect of at last redeeming himself in the eyes of Jane McAndrews, he hopes for a battlefield promotion.

 But Williams is marching into the bloodiest battle of the war - Albuera. As entire regiments are destroyed in the desperate pursuit of victory, the fate of Williams and his comrades hangs in the balance . . .