Another of Perutz's richly detailed, off-angled historical novels (Leonardo's Judas, p. 579, was its predecessor), this one--as in Leonardo--having to do with appearance and reality, of personae manipulated in unexpected ways. During the Peninsular War, units of Napoleon's army are in Spain being commanded by German officers. These officers are arrogant and self-assured--not only in their conviction that they can easily handle the Spanish guerrilla forces but also in their boundless sexual self-satisfaction (each of them having cuckolded the colonel in charge of the regiment). But the colonel's wife now is dead, and when he takes a young Spanish girl as a replacement, the young Turks are confident that history will repeat itself. But that cruel opportunity never occurs: the Napoleonic forces are slaughtered in a general uprising orchestrated by the shadowy Marquis of Bolibar, a nobleman who has planned the foreign army's downfall by use of personal disguise. Who the Marquis is at any one moment is always in doubt--and ultimately deadly. His transubstantiations encourage the foolishness of the officers, and in the end the impersonations come to seem like mass delusion. Period flavor to a fault, much fancy doppelganger thematics--and more murk than probably is necessary--but intriguing nonetheless.