An unusual idea, based somewhat on historical fact, is the centerpiece of John Gardner's ["The Nostradamus Traitor."]…. It is well known that Hitler and some of his high command took astrology and other occultism rather seriously. And anybody who takes occultism seriously is going to take Nostradamus seriously. To this day there are those who believe that the prophecies of the 16th-century astrologer-physician are uncanny anticipations of the future; that everything he predicted has come true.

Anyway, Mr. Gardner has written a book on two levels of time. "The Nostradamus Traitor," an espionage novel in the le Carre or Deighton pattern, takes place mostly in the France and Germany of 1941, in flashbacks, and also in the London of the late 1970's. But most of the book has to do with the exploits of the first British agent to penetrate occupied France. Nostradamus, as the title indicates, plays a...