The Ultimate Secret. The Ultimate Agent. Nathaniel Cade returns.For 140 years, Nathaniel Cade has been the President's Vampire, sworn by a blood oath to protect the President and America from their supernatural enemies. Cade's existence is the most closely guarded of White House secrets: a superhuman covert agent who is the last line of defense against nightmare scenarios that ordinary citizens can only dream of.When a new outbreak of an ancient evil - one that Cade has seen before - comes to light, he and his human handler, Zach Barrows, must track down its source. To 'protect and serve' often means settling old scores and confronting new betrayals . . . as only a century-old predator can.