Blood Will Tell — Jean Lorrah

When Professor Everett Land is found dead, detective Brandy Mather has a puzzle on her hands. The body is definitely his; dental records confirm his identity. But Professor Land is in his forties and the body is that of a very old man. What could have caused him to age so rapidly? Why is the corpse smiling? Brandy enlists the aid of computer scientist Dan Martin, who is smart, handsome, and anxious to help. Dan is almost too good to be true, and Brandy soon falls in love. But something is off about Dan. . . very off. Brandy's investigation soon throws her into the midst of small-town politics, bank robberies, and vampires.