The Rhesus Chart

London’s financial district has always had bloodsuckers, but this time it's literal. In the Laundry—Britain’s secret occult intelligence agency—vampires are dismissed as a joke. That changes when a team of Canary Wharf investment bankers stumbles onto an arcane algorithm that leaves them allergic to sunlight and craving blood. As the cover-up turns violent, intelligence agent Bob Howard is dropped directly into the fallout to contain an outbreak threatening both the city and the agency.