O'Connell's second novel (after Mallory's Oracle) brings back NYPD Sergeant Kathy Mallory, plunging this tough-minded yet soulful heroine into another convoluted case. When a woman killed in Central Park is mistakenly identified as Mallory, the former street urchin and computer whiz sets herself up as bait by moving into the apartment building that houses her three main suspects. Using a computer and the building's electronic bulletin board to psych out the killer, she stirs up more than she bargained for - including someone who wants her dead. Other elements in the intelligent plot include a crime of passion, a suspenseful cat-and-mouse game and a boy who may be telekinetic and whose stepmothers keep dying.