As in Monkey Shines (1983) and Far Cry (1984), Stewart muddies up a swiftly flowing drama--here, father-son tensions as Dad loses his sight--with techno-thriller grit and parapsychological silt. Alerted by migraines to a brain malformation that will soon blind him, Guy Sullivan, proud headmaster of a posh British school, sends girlfriend Lisa away without telling her of his affliction and then enlists the aid of son Jerry--emotionally wobbly due to the recent death of his mom--to prepare for darkness. Initial astonishment that the migraines are accompanied by clairvoyant flashes--i.e., a train crash glimpsed days before the fact--is submerged in Guy's poignant journey to founts of visual splendor: the London Zoo, the Turner collection at the Tate. Too soon, however, blindness strikes; Guy fumbles on as Jerry grows addicted to helping him. Meanwhile, eye-research specialist Patrick Ross is making great strides--via the growth of new brain pathways--in restoring sight to blind animals. When Lisa learns of Guy's blindness, she persuades Patrick to try his technique on Guy. The two men begin a series of exhausting experiments, each step punctuated by a fulfilled premonition. As Guy inches towards sight, a disturbed and frightened Jerry charges into rebellion (""Dad, you're fighting your destiny"") and, finally, subversion, hiding medication and smashing the experimental equipment. When Patrick dies in a car crash, Guy goes it alone with makeshift gear, racing against time in an exciting climax to regain his sight before a final premonition comes to pass. Stewart's sensitive limning of the stormy father-son relationship and of Guy's groping with blindness offers vital fare; too bad it's nearly overpowered by overblown and unnecessary pseudo-Crichton/King scientific/psychic spicings.