harles II is well established at White Hall Palace, his mistress at hand in rooms over the Holbein bridge, the heads of some of the regicides on public display. London seethes with new energy, freed from the strictures of the protectorate, but many of its inhabitants have lost their livelihoods. One is Thomas Chaloner, a reluctant spy for the feared secretary of state, John Thurloe, and now returned from Holland in desperate need of employment. 

London in the spring of 1665 is a city full of fear. There is plague in the stews of St Giles, the Dutch fleet is preparing to invade, and a banking crisis threatens to leave Charles II's government with no means of paying for the nation's defence. Amid the tension, Thomas Chaloner is ordered to investigate the murder of Dick Wheler, one of the few goldsmith-bankers to have survived the losses that have driven others to bankruptcy - or worse.

In the sapping summer heat of 1665, there is little celebration in London of the naval victory at the Battle of Lowestoft. The King, his retinue and anyone with sufficient means has fled the plague-ridden city, its half-deserted streets echoing the sound of bells tolling the mounting number of deaths. Those who remain clutch doubtful potions to ward off the relentless disease and dart nervously past shuttered buildings, watchful for the thieves who risk their lives to plunder what has been left behind.

The plague raging through London in 1665 has emptied the city. The only people left are those too poor to flee or those who selflessly struggle to control the contagion and safeguard the capital's future. Amongst them, though, are those prepared to risk their health for money - those who sell dubious 'cures' and hawk food at wildly inflated prices. Also amongst them are those who hold in their hands the future of the city's most iconic building - St Paul's Cathedral.

Hugh of Singleton, fourth son of a minor knight, has been educated as a clerk, usually a prelude to taking holy orders. However, feeling no certain calling despite a lively faith, he turns to the profession of surgeon, training in Paris and then hanging out his sign in Oxford. A local lord asks him to track the killer of a young woman whose bones have been found in the castle cesspit. She is identified as the impetuous missing daughter of a local blacksmith, and her young man, whom she had provoked very publicly, is in due course arrested and sentenced at the Oxford assizes.