The prolific and versatile Shepard (Batting Against Castro, 1996, etc.) offers in his intermittently enthralling fifth novel an empathetic fictionalized biography of the great German silent-film director F. W. Murnau (1888--1931). Born Friedrich Wilhelm Plumpe to a deeply bourgeois Westphalian family, Shepard's protagonist is first seen, in 1907, as a reluctant student of philology at Charolottenburg, where he meets the invincible and sophisticated Hans Ehrenbaum-Degele, a budding poet who will become Wilhelm's schoolmate, soulmate, and lover--and whose aestheticism will encourage the self-created ""Murnau"" (the name of a Bavarian resort the two visit) to pursue his interest in the theater. These early pages are superb: Shepard has so thoroughly mastered the idiom and feel of the period that we seem to be inside a young Thomas Mann novel. The narrative then proceeds both through flashback (showing Wilhelm's unhappy boyhood) and straight chronology, moving forward first to Murnau's apprenticeship at Max Reinhardt's theater school in Berlin, his disturbing intimacy with such decadent eminences as poet Else Lasker-Schuller and homosexual film actor Conrad Veldt. There are splendid accounts of Murnau's wartime service as a fighter pilot (during which he ""came to understand aviation as a new way of seeing"") and later of the preparations for and filming of his vampire movie Nosferatu (a memorable vision of""The natural world operating under the shadow of the supernatural."" But, alas, the story's second half unconvincingly telescopes the remainder of Murnau's (admittedly brief) career and life: the filming of Der Letzte Mann, distinguished by its use of a moving camera devised by his brilliant cinematographer Karl Freund; his star-crossed Tahitian collaboration (on Tabu) with documentary filmmaker Robert Flaherty; and his death following an auto accident. This should have been a terrific novel--and a longer one. Its images simply flicker by so quickly that its power to involve and move is frustratingly dissipated.