Boston PI Sunny Randall is the daughter Robert Parker's series hero Spenser and his inamorata, Susan Silverman, might have had if they weren't so busy parenting Pearl the Wonder Dog. Like Spenser, Sunny is smart, tough, and fearless; like Susan, she's sexy, droll, and vulnerable; and like Pearl, Sunny's pit bull, Rosie, is the only character who's wise enough to hide when trouble comes knocking at the door. In Shrink Rap, Sunny's working as a bodyguard for a famous romance writer who's being stalked by her ex-husband, a psychiatrist engaged in extremely unprofessional conduct with his female patients. To get the goods on Dr. John Melvin, Sunny goes undercover as a vulnerable divorcée, which isn't that far from the truth; simultaneously, she's also seeing another therapist, who's supposed to be coaching her for her undercover role but is also helping her understand her troubled relationships with men. It's a clever device, and Parker makes the most of it in this spare, smart, swiftly paced mystery, one of Parker's best in recent years. --Jane Adams