In a memoir on an uncharacteristically somber subject, Trillin (American Stories, 1991, etc.) traces the life of his college friend Roger ``Denny'' Hansen: Phi Beta Kappa, Rhodes Scholar, possessor of charm and good looks to spare--and, at age 55, a suicide victim. Denny had seemed such a golden boy that he was photographed by Alfred Eisenstaedt for a Life feature on his 1957 graduation from Yale, and his classmates joked about serving in his cabinet when he became President. But life didn't work out that way. Drained of his confidence at Oxford, unable to enter the Foreign Service as he had desired, Denny (now known as ``Roger'' to new acquaintances) fell into a succession of jobs as an itinerant foreign-policy specialist before becoming a professor of international relations at Johns Hopkins's School of Advanced International Studies. In his last years, old friends were puzzled by his broken dinner engagements and unreturned phone calls; new associates found him an unsmiling, moralistic nag who never quite fit in. Why did Denny finally kill himself? Because of unbearable back pain (as implied by a suicide note), a dead-end academic specialty, lack of family or loved ones, long-repressed homosexuality--or, as one friend noted, simply because he was ``depressed all of his life''? After searching for the point of no return in his old friend's life, Trillin wisely settles for no easy conclusions (``Roger would have said that you didn't know him at all,'' one lover of Denny's remarks--with which Trillin ruefully agrees). What makes this gloomy post-mortem bearable and even fascinating is a smattering of Trillin's one- liners, as well as shrewd observations on sexual orientation, changes in universities' demographics, and American attitudes toward success. Perhaps more appropriate as one of Trillin's shorter New Yorker pieces--but, still, a fine meditation on one life's aborted promise, the crippling burden of anticipated success, and the mysteries of the human heart.