Necroscope

When young Harry Keogh discovered that he was a Necroscope - someone who can communicate with the dead - he was astonished. He grew more astonished as the years passed and his dead friends - the world's greatest artists, scientists, inventors, and thinkers, not to mention ordinary folks like Harry's own dear, departed Ma - bestowed on him their knowledge and their love.
He also learned how to transport himself instantaneously through time and space, with the power of his mind alone, but not all the gifts he received were so wonderful. There was terrible knowledge to be had.
Mankind was being preyed upon by terrible vampires who hunted humans for their blood. Some people became victims of macabre "experiments" that rendered them unrecognizable as human beings. Others were kept as servants or playthings.
Harry Keogh swore that he would become man's greatest defender, that he would destroy every last vampire.
But the price of this war was high. Many of those Harry loved and respected were corrupted, killed, or lost - including his own wife and son - vanished in the heat of battle. Harry's search for his family began in Necroscope: The Lost Years. It ends here.