Is somebody at Boston Memorial Hospital killing post-surgery patients by messing with their IVs? So it seems. Pathology resident Robert Seibert has found a pattern of unexplained deaths following cardiac surgery--many of them involving homosexual, mentally defective, or terminally ill patients. And the obvious suspect (to the reader, not anyone in the book) is the husband of Robert's psych-resident pal Cassi Kingsley: Dr. Thomas Kingsley, Boston Memorial's top cardiac surgeon, a three-bypass-a-day man who's secretly popping pills (Dexedrine, Peroodan) and forever complaining about the OR time devoted to hopeless ""teaching"" cases. Furthermore, Cook (Coma, Fever, etc.) gives Dr. Kingsley a smothering cartoon of a mother: she virtually lives with Thomas and Cassi, demanding that her super-successful son be ever more perfect. So, though wimpy heroine Cassi--a beauty with diabetes and eye problems--is laughingly slow on the uptake, it's soon obvious that Dr. K. (who's alternately impotent and adulterous) is out of his skull; and when Cassi tries to help him with his drug problem, he has a predictably paranoid reaction. Is Cassi herself in danger, then? You bet--especially since both she and Robert, by coincidence, will be having surgery (eye and wisdom teeth respectively) at the hospital during the same week. Robert's the first to go--killed by ""the man,"" a still-unidentified doctor, in his hospital bed. Then eye-patched Cassi is being terrorized in her post-op hospital room (she smells Thomas' cologne!)--and next, at home, has an insulin-reaction attack in a house where the phones are out of order. . . which leads to a mad hospital dash and a showdown/confession with the unrepentant killer. (""All I want to do is surgery on people who deserve to live, not a bunch of mental defectives. . . ."") Cook makes a few feeble attempts to cast suspicion on some of Thomas' colleagues--but the plotting throughout is crudely transparent, in the slipshod gothic/psycho vein; and dumbo Cassi is the weakest of all Cook sleuth-ettes. Still, the hospital detail is varied (autopsies, shrinks, diabetes, cardiac galore)--and, though lacking the sci-fi-ish tension of Coma or Brain, this is less morbid than Fever: messily readable (if dreadfully written) comic-book suspense that noisily rattles the old/new clichÃ‰s about surgeon-as-dangerous-God-player.