Lightbreaker

From the back cover of the Night Shade first edition: "Markham has returned to Seattle searching for Katarina, the girl who, a decade ago, quite literally tore his soul from his body. What he discovers instead is dark magick of an ancient and destructive kind. His encounter with a desperate spirit leaping destructively from host to host set Markham on the trail of secretive cabal of magicians whose past is strangely linked to his own. Armed with the Chorus, a phantasmal chain of human souls which he wields as a weapon of will, Markham must engage in a magickal battle whose stakes prove to be earth shatteringly high."