A risk taker with a protean imagination, Shriver (The Post-Birthday World) has produced another dazzling, provocative novel, a witty and timely exploration of the failure of our health-care system. Shep Knacker's long-cherished plan to use the million dollars from the sale of his handyman business to retire to a tropical island receives a gut-wrenching blow when his wife, Glynis, is diagnosed with a rare cancer. Transformed into a full-time caregiver, the good-natured Shep is buoyed during the illness of self-centered, vindictive, and obnoxiously demanding Glynis by his working mate and best friend, Jackson Burdina, whose teenage daughter, Flicka, also has a terminal disease. Ironically, Glynis tenaciously clings to life, while Flicka, with whom she bonds, wants to end hers. Jackson, meanwhile, acutely conscious that he's going broke, rails pungently against government regulations and the insurance industry. A mouthpiece for the plight of middle-class workers, Jackson's diatribes about contemporary society—the medical, educational and banking systems, exorbitant taxation, political chicanery—ring painfully true. As Shep's Merrill-Lynch account dwindles and further medical calamities arise, Shriver twists the plot to raise suspense until the heart-lifting denouement. (Mar.)