The operation proceeds smoothly. Snip, and the weakened section of Genghis Mao’s aorta comes out. Stitch stitch, and the replacement is grafted in. Heart-lung machines keep the circulation bubbling. The Khan watches, conscious and beady-eyed, through the whole thing, now and again nodding to himself as Warhaftig executes some particularly admirable veronicas and entrechats and passades. He seems to know what is going on; he has spent more time observing surgeons at their trade than I have, Shadrach realizes, and can probably do the job pretty well by himself by now. Warhaftig’s elegant fingers elegantly close the incision. The tissues are raw and reddening, having been cut into for the liver transplant less than two weeks earlier, and this calls for some special prophylactic measures, but the surgeon brings everything off with his customary finesse. Genghis Mao grins approval when all is over. “Good show,” he tells Warhaftig. “Two ears and the tail!”

Shadrach makes off with the Khan’s discarded abdominal aorta. He tells Warhaftig, not that Warhaftig cares, that he intends to run some tests on it, but what tests would tell him anything about this drooping length of ancient tissue, this tired hose, that he doesn’t already know? He covets it because it’s an authentic piece of the body of the authentic Genghis II Mao IV Khan, and Shadrach has the collector’s itch: this will be an ornament to his little museum of medical memorabilia. A relic of one of history’s most famous patients. There is a tale Shadrach knows, probably apocryphal, of how the doctor who performed the autopsy on Napoleon removed the imperial penis and kept it as a souvenir of the late emperor, bequeathing it to a fellow physician who ultimately sold it at an immense price, and so on and on, passing from one doctor’s collection to another, until it disappeared altogether during the confusions of some twentieth-century war. Similar stories, he knows, have been told of odd scraps of Hitler, Stalin, George Washington, Catherine the Great. Shadrach regrets that he attained his present post too late to collect some of the really significant organs of Genghis Mao — a kidney, say, or a lung, the liver, the pancreas — but all of them were gone long before Shadrach’s time, the native organs of the Khan’s body removed and replaced, sometimes several times over, with transplanted substitutes. Shadrach does not see much value in preserving Genghis Mao’s fourth liver in his collection, his eighth spleen, his thirteenth kidney, though he recognizes that these temporary residents of the Khan are more intimate artifacts of Genghis Mao than, say, his bedroom slippers or his wristwatch. But he prefers the genuine somatoplasm, and a piece of authentic aorta is the best he can do just now.

There’s the aneurysm, big and ripe, ready to pop. Another few days and it might have ruptured, poof! and no more Genghis Mao. The Chairman and Mangu might have shared the same funeral, come Saturday, if Shadrach hadn’t felt odd twitterings in the circulatory-system sensors and correctly guessed their import. So I have saved the Khan’s life, not for the first time and he is once more restored to perfect health. Fine. Fine. May he live five hundred years, and may I be his physician always!

Alone in his office, ruminating over his medical treasures, his books and old instruments and now this bit of bottled aorta, Shadrach feels safe and comfortably entrenched. This Avatar disturbance will blow over. The Khan, after all, is conservative; he will cling to his own Mongol body, the well-loved and sturdy patchwork carcass, as long as he can, whatever the temptations may be for him to jump into Shadrach’s strong, young, and vital frame. So there will be no precipitous exit for Shadrach, and in the months or perhaps years ahead he can try to shift the Khan’s fantasies entirely away from Project Avatar and toward Project Talos. Which will mean aborting the researches of Nikki Crowfoot, but Shadrach can’t feel too guilty about that, all things considered.

He gives the aorta pride of place on his shelves. Centuries from now it may be sacred, enshrined in a reliquary of ivory and platinum, and the groveling faithful will chant thanks to the sainted Shadrach Mordecai for having saved for posterity this shred of divine meat. Who knows? There is an apocryphal story that many of Genghis Mao’s original organs are preserved in some labyrinthine secret tunnel, kept in cold storage or perhaps maintained in vivo, for eventual use in cloning the Khan. Shadrach doubts this. If Genghis Mao had any serious interest in being cloned, huge budgetary appropriations would be going to support tissue-culture research, and, so far as Shadrach knows, not much is going on in that area. Or, more likely, there would already be a battalion of genetically perfect duplicates of Genghis Mao lying in suspension tanks on five or six continents, waiting to be summoned into life.

Mordecai has often thought of writing a scientific monograph on his patient, a medical biography of Genghis Mao, a full record of the myriad transplants and implants, the infinity of surgical jugglements, that are responsible for the Khan’s longevity and perhaps for his terrifying vitality. There would be nothing in the literature to compare with it, not even Beaumont on Alexis St. Martin’s digestive tract, not even Lord Moran on Churchill: had ever there been so single-minded and long-sustained a medical effort, spanning so many decades, to keep one human being alive and well? Already the achievement verges on the miraculous, but the real miracles stilllie ahead, as Genghis Mao, ageless and eternally renewed, lives on to be a hundred, a hundred ten, a hundred twenty. There is another, greater temptation — to write not merely a medical study but a full-scale account of Genghis Mao’s life. No biography of the Chairman exists, other than vague, sanitized publicity pamphlets, mere recitals of his political accomplishments and other exterior events, avoiding all details of his private life. It is as though the Khan has a superstitious fear of having his soul captured on paper. And so Shadrach’s impulsive fantasy: to nail the Khan in words, to pin him down with literary juju: It is one means of gaining control over the world’s most powerful man, at least in a metaphorical way.

The trouble is, no source material is available. The computer banks of Ulan Bator are gorged with intimate data about every human being alive — except Genghis Mao. Press the right button and platoons of facts march forth — but none about Genghis Mao. The facts of his life are unknown and may be unknowable, beyond the most elementary public milestones, his promulgation of the philosophy of centripetal depolarization, his founding of the PRC, his election to the Chairmanship. All the rest has been suppressed, even obliterated. When was he bom? In what obscure village? What was his childhood like, what were his boyhood ambitions? What was his original name, in the old People’s Republic days before he proclaimed himself to be Genghis Mao? What was the early course of his career? What sort of education did he have? Did he ever travel abroad? Was he ever married? A father? Yes, that’s a good question — are there, somewhere in Mongolia, middle-aged men and women who are in fact the blood children of Genghis Mao, and, if so, do they know who their father is? No one can answer these questions. No one can answer any questions about Genghis Mao except with hearsay, apocrypha, and myth. He has very carefully covered his traces, so carefully that the utter success of the attempt at total concealment argues a kind of madness.

But is anyone, even Genghis Mao, really willing to expunge from the world all traces of his private self? Criminals are said to return compulsively to the scene of the crime; possibly those who seek to shroud themselves in mystery tend also to undo their own mystifications by burying, for history’s sake, a full account of all they have tried to hide. Is there no place where Genghis Mao has secreted a concealed record of everything he has kept from the knowledge of his subjects? Say, a diary, an intimate and revealing diary, a repository for the essence of Genghis Mao’s masked soul. Shadrach imagines himself stumbling across such a document among the Khan’s effects — a single billion-bit bubble-chip, smaller than a fingertip, on which is implanted the raw red stuff of Genghis Mao’s life, his confessions, his unvarnished memoirs, out of which the faithful doctor Shadrach Mordecai will construct the first and only true account of the strange and sinister man who came to dominate the dying civilization of the early twenty-first century.