Seattle p.i. Thomas Black's chance reunion with Kathy Birchfield, the lawyer whose fiancÇ he accidentally killed last year, is ruined when Kathy runs over her own client, 70-something Marian Wright, a sleuth who was gathering information on three men for women with a view toward revenge. The men: (1) the University of Washington student who humiliated and traumatized Juanita Raykovich 20 years ago; (2) the Sun Valley man calling himself Eddie Murphy who left Susie Scudder pregnant; and (3) Marian's own husband, Chuck, who died after infecting her with HIV. Though the histories of Marian and her two clients keep intersecting in unnerving ways, Marian's search for a ``tree of death'' tracing the course of the HIV infection backward from Chuck through a daisy chain of sex partners is the primary focus here--and a mordant one it is, with nearly everyone, including Thomas and Kathy, apparently only two or three couplings removed from the plague, and with everyone listed in the tree of death issuing frantic denials, and perhaps willing to kill to back them up. The plot, as Thomas acknowledges, is nothing more than a distaff spin on Emerson's own Yellow Dog Party (1991). But the p.i.'s eighth case, if not the equal of The Portland Laugher (1994), still digs deep into some painful new territory.