Combining hand-wringing angst with wild improbabilities, Edgar-nominee MacDonald (The Unforgiven, etc.) plunges her heroine, Keely Bennett, into a nightmarish ride through domestic bliss gone bad. First husband Richard, who suffers from horrible migraines that nothing seems to help, finally commits suicide. Their nine-year-old son, Dylan, finds his bloody body. To the rescue comes lawyer Mark Weaver, a childhood friend of Richard's, who not only steers Keely through the legal and financial problems caused by Richard's suicide but also woos, weds and sweeps Keely away to a new life in generic St. Vincent's Harbor. Five years pass, giving Keely and Mark a delightful baby girl and a surly and troubled teenage son/stepson. Then a tragic accident leaves Keely widowed once again, and a vengeful district attorney, Maureen Chase, to whom Mark was engaged before he left her for Keely, is determined to find Dylan guilty of more than teenage negligence in order to get even. Everything seems stacked against Keely and her alienated son. As their situation grows more and more desperate, Keely becomes more and more determined to protect and defend Dylan. The heroine fighting against frightening odds and against unseen enemies is fine, and MacDonald rings some nice changes on her set of bells. But she also relies too heavily on unconvincing coincidences that seriously, perhaps fatally, weaken the suspense. 5-city author tour. (Apr. 2)