Neurosurgery viewed as the paradigm of modern medicine in its increasing control over the unknown, the uncertain, and the unexpected. During a three-year period, Sylvester (Target: Cancer, 1986, etc.) spent thousands of hours at Barrow Neurological Institute in Phoenix, many of them in the company of its director, Robert Spetzler. Barrow is one of the country's leading centers for neurosurgery, and Spetzler, a fiercely competitive neurosurgeon, is intent on improving its reputation even further. What Spetzler and his team at Barrow do better than anyone else is hypothermic arrest, or ``standstill,'' in which the patient is put into a deathlike coma to reduce the brain's need for oxygen. The heart is stopped, the brain chilled, and then blood drained from the body for about an hour to give the neurosurgeon an opportunity to operate--to ``thread a cobweb through a shadow''--in a blood-free environment. Bringing the patient back is complicated and difficult, and the results are often less than perfect. That it can be done at all owes much to sophisticated technology-- magnetic resonance imaging, CAT scans, intraoperative microscopes, and 3-D cameras--as well as to the skill of the neurosurgeon and a team of cardiologists, anesthesiologists, and various nurses and technicians. Amid the hi-tech wonders and high-pressure competitiveness that characterize neurosurgery, patients can be in danger of becoming little more than means to an end. But not to Sylvester, who keeps his sharp reporter's eye on the human beings under the knife. An absorbing report that provides an extraordinary view of the wondrous human brain, contains compelling operating-room scenes, and shows us something of where neurosurgery has been, where it is now, and where it's headed.