After having faced down vampires in the previous novel, Laura Caxton is more than happy to continue her career as a trooper in the Pennsylvania State Police. Her life is upended again U.S. Marshal Special Agent Jameson Arkeley contacts her to help investigate the discovery of a cache of Civil War-era coffins underneath the grounds of the Gettysburg Battlefield. There are one hundred coffins in the underground crypt along with ninety-nine hearts removed from the moldering vampire bodies, but one coffin is smashed and the vampire body is missing. Hobbled by his crippled hand, Arkeley presses Caxton into service as his field operative to hunt down the missing vampire body before another horrific outbreak of vampirism infects the local population.
In a series of flashbacks told through letters, journals, and military reports it is revealed that the 150 year old vampires of the remains of a Union Army vampire corps that was used to turn the tide against the South at Gettysburg. Promised to be revived as human once a cure for vampirism was found, the soldiers were imprisoned in their tomb and were almost immediately forgotten by their commanders. The archeologist who discovers the tomb uses the vampires in a plot for his own personal gain.