Former Saturday Night Live writers Patricia Marx and Douglas G. McGrath take aim at Hollywood in this wicked, satirical novel about the making of the flop of flops.   Through the 1930s and 40s, X. Y. Schwerdloff brought us the best: the best comedies (Let's Play Golf), the best dramas (Surprise Witness), the best musicals (Sing-a-ling), even the best World War II propaganda (Tokyo, Kansas).   But by the 60s, the legendary Schwerdloff studio had fallen on hard times. To get out of accepting an assignment at the studio, many actors served in Vietnam. Fugitives liked to appear in a Schwerdloff film because they would be safe from being seen.   Now, it is up to Bucky Schwerdloff to save his father's studio. He must produce a blockbuster. To do so, he hires the most successful director in Hollywood, Ferris Keneally, whose last film, The Blinkies, broke box office records. Bucky promises Keneally that he can make whatever film he wants.   Thus begins the hilarious drama of the most breathtaking flop in Hollywood history. There has never been a film to match Keneally's version of The Pilgrim's Progress, about which one film critic wrote: "You are mesmerized by it . . . the same way you can't take your eyes away from a bad car accident." "One of the most original and witty takeoffs on Hollywood . . . a delicious read."--Judith Crist