Twenty stories and poems from famous names--many of whom seem to have pulled unsaleable material from the trunk--and a few newcomers. Ray Bradbury offers a pretentious theological poem, written originally ""as a Christmas greeting to his legendary friends."" (Williamson's introductory notes throughout are gushily fawning, in the mutual-admiration-society mode.) Gene Wolfe, known primarily for science fiction, contributes a limp psycho-crime anecdote. Robert R. McCammon, an erratic horror-novelist (the fine Mystery Walk, the wretched Usher's Passing), is represented by an overwrought Vietnam-vet chiller--with the vet's traumatic dreams conjuring up monstrous ""Nightcrawlers."" Of all the well-known writers here, in fact, only Ray Russell seems to be in secure form, in the minor but blessedly stylish ""Czadek."" And the only promising item from the newcomers is David B. Silva's ""The Turn of Time""--awkwardly written (like so many of these genre pieces), but creepily imagined. A generous but fairly weak horror/fantasy anthology, then--also including a Psycho retread by Robert Bloch, a mildly horrifying worldwide plague from F. Paul Wilson, an interview with Richard Matheson, a tribute to Charles Beaumont. . . and an amusing but overextended alien-in-the-classroom tale by Gahan Wilson.