As Gregor Demarkian's Philadelphia neighbor Donna Moradanyan lurches toward her dubious wedding--will she go through with her vows to faithful cop-turned-lawyer Russell Donahue, or will she get waylaid again by irresponsible Peter Desarian, father of her son Tommy?--marriages seem to be flying apart all over the gated suburb of Fox Run Hill (""the kind of place men moved with their second wives""). Diet guru Henry Adder and his gargantuan wife Evelyn are the bane of each others' existence; Molly Bracken's just had another abortion she's kept secret from her downscale husband Joey; Sarah and Kevin Lockwood have run completely through Sarah's sterling old money; and Patsy MacLaren Willis has just shot her husband, withdrawn $15,000 from their checking account, and disappeared--though not before parking her Volvo in a downtown parking lot with a pipe bomb ticking away inside. The two stories would have nothing to do with each other if it weren't for the impending show of high-flying Karla Parrish's photographs, which reunites Karla and her Vassar friend congresswoman Julianne Corbett with local alumnae Liza Verity, R.N., and Patsy MacLaren (oops), and also drags serial-killer specialist Gregor (And One to Die On, 1996) into a rash of murderous pipe bombings. Gregor's repeated teasing hints will make the solution obvious even to non-Armenian readers. The real loss, though, is all those misfit Fox Run Hill matrons, springing to life in a superbly alarming prologue and then left idling at high through most of the subsequent proceedings.