Sequel to Spruill's Rulers of Darkness (1995), a fresh medical suspense/horror novel and the start of a new series about hemophages (bloodeaters) in the District of Columbia. Again, Spruill gives himself a hospital setting to work with--though the various medical analyses of vampire blood and other occult arcana, touched on in that earlier novel, are unsurprising. Nor does the plot leap forward as electrically as in Rulers. With historical background no longer new, the story focuses now on a 500-year-old hemophage's revenge on his father, himself a thousand-year-old bloodeater. Ten years have passed since the action in Rulers. D.C. homicide detective Merrick Chapman has retired, having married hematologist Katie O'Keefe and fathered a nonhemophagic son with her. Several hundred years before, Merrick turned on his kind and began locking fellow vampires up in vaults from which they could not escape and in which they eventually starved to death. To help locate bloodthirsty hemophages, who disguise their trails, Merrick turned to law enforcement and became adept at picking out vampiric victims from other homicides. His greatest enemy now is his son Zane, who refuses to be turned from vampirism. Ten years ago, Merrick confined Zane in an escape-proof vault, where he should have died after two years without feeding. But in some mysterious manner Zane has now escaped and is out to return his daughter, Jenny Hrluska, to the bloodlust natural to her. Jenny, however, now 22 and the youngest intern ever at Adams Memorial, wants to save lives, not take them. She sides with her grandfather Merrick, who hopes to die a normal death along with his wife Katie (he has watched 16 wives and 43 children grow old and die). But then Zane commits a murder attributed to Jenny, trying to force her back into the fold and to lure his father to his destruction. Less energy and richly layered excitement than before, but still notable in its field.