The Woman Who Fell from Grace — David Handler

THIS PEN FOR HIRE.
Once, Stewart "Hoagy Hoag was the toast of the publishing world and husband of luscious Broadway beauty Merilee Nash. But fame and fortune left him as swiftly and surely as Merilee. Now Hoagy ekes out a living as a ghostwriter of celebrity memoirs and reluctant amateur detective, aided by his cat-food-eating basset hound named Lulu.

IT'S THE BOOK AMERICA IS DYING TO READ...AND IT MAY JUST BE THE DEATH OF HOAGY.
Published fifty years ago, Alma Glaze's Oh, Shenandoah wasn't the greatest novel in the history of the written word, but it certainly was the most popular. The public's continuing fascination with the book and movie is nearly equaled by its morbid curiosity about the tragic deaths of the film's handsome young star and the novel's author. Now Hoagy's come into the ghostwriting job of a lifetime: penning the surefire blockbuster sequel to Oh, Shenandoah, with the approval of Alma's formidable daughter, Mavis Glaze. All he has to do is deal with Mavis's collaborator from another dimension, enough family loathing to fill several books, rumors of foul play and cover-ups half a century past, and several all-too-fresh murders. All Hoagy has to do is finish the book... before the book finishes him.