MELANCHOLY BABY Boston P.I. Sunny Randall-as conflicted as she is beautiful-helps a troubled young woman locate her birth parents only to uncover some dark truths of her own.  My ex-husband was getting married to a woman I wanted to kill. I didn't actually know her, and killing her would only make matters worse. But I got as much pleasure out of the idea as I could before I had to let go of it.  And so begins Melancholy Baby, the fourth novel in the  bestselling series featuring Sunny Randall who now  faces the unthinkable: the marriage of her ex-husband, Richie, to someone else. Despite the formality of divorce, Sunny and Richie's relationship had continued, in its own headstrong way, until Richie's desire for marriage overtook Sunny's need for freedom. So when college student Sarah Markham comes asking for help in finding her birth parents, Sunny realizes she must take the case, if only to distract her from her personal life.  But life and work have a curious-and dangerous-way of intersecting. Before the investigation has a chance to take off, two key players are dead, and Sunny is back on a psychiatrist's couch, probing her own past for clues. What she discovers has the potential to shatter Sarah Markham's family and destroy her sense of self, while Sunny's own beliefs are put to the ultimate test.    Emotionally complex and rich with insight, this is the Grand Master at his storytelling best.