"Kelowna, British Columbia, 1969. A sonic boom from an overly-exuberant air show shatters every window in town. The American Navy, accepting responsibility for the accident, offers apologies and reparations—neglecting to mention the link between the disturbance in the air and a stray bit of medieval Hungarian regalia kept under guard at Fort Knox since the Second World War. Even quieter are the rumors that the boom and the crown might also be related to a new and deadly infection brewing in the Caucasus.
When John Willcox, happily unoccupied in London, is informed of the boom, the crown, and the contagion, he vows to keep himself well away from the investigation. When his sister, Lydia, joins forces with the disagreeable Richard Maugham, however, he bows to necessity and accepts that he can’t escape his responsibilities."