It isn't bad enough that leukemia-research Nobelist Dr. Jonathan Griscom is gunned down on the hard-case Roxbury street he was trying to help rehabilitate; as soon as his dithery widow Jane announces her plans to open a daycare in the neighborhood, she's shot too. As Jane hovers between living and dying, Olivia Chapman, the Boston decorator who supposedly made the appointment that lured Jane to the shooting, decides to clear herself by taking on the Griscom gang (venture capitalist Francesca, threadbare musician Benjamin, health-foods promoter Gordon, rolling-stone dilettante Anne, and their equally beastly spouses and hangers-on); and resultant sparring -- intensified by the reappearance of Jane's long-lost son Keith Somers -- is delicious. The mystery's more substantial than in Logan's earlier outings (C.A.T. Caper, 1990, etc.), but the real pleasure here is watching Olivia -- who's as tough-minded and resourceful as she needs to be -- keep landing miraculously on her feet until the fadeout.