At dawn one morning in 1933, an amateur dowsing team digging the banks of the Thames for precious metals unearths the body of a young woman with a missing toe and a priceless gold coin in her mouth. The case falls on Assistant Commissioner of Scotland Yard Joe Sandilands' turf, but he's been given another assignment - and a very high-profile one. London is hosting a historic global economic conference to try to solve the global Depression and political tensions are running high. Sandilands' job is to protect and keep an eye on the visiting American senator Cornelius Kingstone.