Rich, Radiant Slaugh

True-crime writer Patience (Pay) McKenna, returns ( Death's Savage Passion et al.) in another sophisticated adventure edged with terror. This time she's in Baltimore with writer friends, appearing at a benefit in a bookstore called ``The Butler Did It.'' The occasion is a charity drive for the homeless but it turns into a mystery when the body of an obstreperous woman is found in the store. Among the literary lights present are several disagreeable persons who could be killers, Pay suspects, but she fixes her detecting insights on others in attendance, including eccentric near-billionaire Jon Lowry and Christopher Brand, an irascible Pulitzer Prize-winner who supplies the smash finale to Papazoglou's fourth tour-de-force. (Dec.)