In the rural peace of modern England a war game recreates the slaughter of the Civil War. But when the battle ends, a real corpse is left it the Swine Brook; and an aristocratic but impoverished revolutionary claims to have found a cache of 'Cromwell's gold'. When David Audley is called in, 17th century secrets and the deadly game of modern espionage clash in a brilliantly intricate thriller of bluff and counter-bluff.