For authors who keep on writing into old age, both their strengths and their weaknesses tend to become exaggerated (as can their critical reception, either pro or con). The Lawgiver, the latest novel of Herman Wouk, the ninety-seven-year-old author of Marjorie Morningstar and The Winds of War, is a case in point.

A religious Jew, Wouk has been among the most popular and prolific novelists in American history, yet he counted among his regrets the fact that he never wrote a book about Moses.

Now here it is. Not far from his eleventh decade, he has produced a novel that deals, if only obliquely, with the Biblical patriarch. Wouk’s more immediate subject is one Margo Solovei. A Hollywood film director known for making small-scale comedies, Margo has been charged by Louis Gluck, an Australian mining tycoon, with making a big budget spectacular about the central figure of the Book of Exodus. Charming and plucky but hardly the outsized tyrannical personality that such a task might ordinarily call for, our heroine fears that she is in over her head. This is not her only concern. Through the course of Wouk’s story, Margo must also resolve her unconsummated yearning for Josh Lewin, a corporate lawyer whom she met years earlier.

Wouk offers his story in epistolary form, and he includes himself as a subsidiary character, an advisor on the prospective motion picture. Trying to keep current, Wouk uses Skype call transcripts, emails,