Necroscope

Harry Keogh, the Necroscope, the man who can talk to the dead, and Earth's greatest vampire hunter, has been searching for his wife and infant son, gone missing during Harry's war against the vampires. This obsession has left him open to subtle influence by an ancient vampire, Radu. Entombed in amber, trapped in undeath, Radu plans for his resurrection and plots the destruction of other vampires who might challenge his supremacy.
Thus, Radu's enemies are now Harry's--and Harry cannot properly defend himself. His powers--his deadspeak and his ability to transport himself through the Mobius Continuum--are locked away in the recesses of his vampire-clouded mind.
But Harry is not without allies, living and dead. E-Branch, the psychic spy organization, is worried about Harry. So is harry's long-dead Ma, and the ancient philosopher and prophet Nostradamus, whose centuries-old quatrain make eerie sense in the modern world.
Right now, Harry Keogh doesn't even know he's the Necroscope. But Earth's teeming dead won't let him forget them for long--and won't let him forget that Radu and his vampire kind are humanity's deadliest enemies.