Zaleski's Percentage — Donald MacKenzie

Zaleski is a middle-aged philanderer determined to retrieve the Virgin's Dowry, a jeweled monstrance worth 500,000, which has reappeared for display in an art gallery in Conduit Street in London. This ageing Polish patriot carries out the crime but in doing so becomes the target for Detective Inspector John Raven of the CID - one of the most ruthless and capable policemen on the force. 'Perfectly fascinating and perfectly written' Chicago Sun Times