'The Last Theorem' by Arthur C. Clarke and Frederik Pohl

The most exciting part of "The Last Theorem" (Del Rey: 304 pp., $27), the novel by the late Arthur C. Clarke and fellow science fiction veteran Frederik Pohl, has nothing to do with the titular titillation of finding a proof for Fermat's famous marginal musing, nor with a secret weapon called Silent Thunder that instantly renders all of North Korea a demilitarized zone, nor with the umpteenth invocation of Clarke's famous "space elevator" concept, which substitutes traditional rocket launchers with a giant ladder to the heavens. (For these, you need look no further than Clarke's other 2008 collaboration, "Firstborn," with Stephen Baxter.) Rather, "The Last Theorem" involves a part of the Clarke legend that has long been acknowledged but rarely discussed.

By the time of his death in March, the 90-year-old Clarke had presented readers with myriad visions of the future, at once awesome and sobering, in books like "Childhood's End" and the germ and eventual novelization of "2001: A Space Odyssey." Mankind regularly gets a reality check upon contact with vastly superior races, finding itself instantly demoted from center-of-the-universe status to a mere means to an inscrutable end. In the grand scheme of things, the interior life of his characters is insignificant.

Not surprisingly, his private life was excluded from the universe of his books. Though it seems an open secret among many that he was homosexual, Clarke was coy regarding his sexual orientation. (Asked if he was gay, he would respond, "No, merely mildly cheerful.") Any link between his books and this facet of his life remains obscured.

Thus the reader is caught off guard by "The Last Theorem." In this first posthumously published work, Clarke delivers a bombshell in the first chapter. "The Last Theorem's" ostensible protagonist is Ranjit Subramanian, a smart, "good-looking" Sri Lankan whom we meet at age 16. (Clarke lived in Sri Lanka for more than 50 years and died there.) Already the temperature of the prose is several degrees warmer than in a typical Clarke novel: "[H]is skin color was the rich dark brown of a spoonful of cocoa powder, just before it went into the hot milk."

Ranjit and his best friend have become lovers over the first few pages. Soon enough, Ranjit awaits a lecture from his father: "It could have been avoided entirely if he had only remembered to lock his bedroom door so that the porter at his university lodgings would not have been able to blunder in on the two of them that afternoon."