Labor Day weekend on Nantucket Island can be murder. Just ask Detective Meredith Folger, who wants to know why somebody would've killed newly returned Rusty Mason--who took off for Brazil ten years ago one jump ahead of a sealed indictment--and why he would've risked his freedom to come back in the first place. The deeper she digs, though, the more dirt she finds. The resourceful Rusty was blackmailing his kid brother Peter, off-islanders Schuyler Tate-Jackson (Peter's lawyer) and Mayling Stern (Sky's dress-designer girlfriend), and whoever else was implicated in his own mysterious crime back in 1982, just before his father narrowly survived a takeover bid for the family business and then succumbed to a fatal heart attack. And since Merry has problems with her own family business--she's a third-generation cop whose father, the island's chief of police, doesn't want her to handle the case--she can understand how family passions might have boiled over, even before she knows exactly which passions they are. Less purely evocative and more sturdily constructed than other recent regional mysteries--Philip Craig's Off Season (p. 590) and John Smolen's Angel's Head (p. 593)--this is a well-crafted, workmanlike debut.