The Carrington Incident — Niven Busch

Mr. Big, the leader of a powerful and dangerous new movement in Germany, is a seductive orator with a godlike remoteness intent on luring Bertha Carrington to his lair using a handsome young captain as bait. Bertha―tall, blond, Junoesque―is a teacher from America who is visiting Germany as the chaperon of a rich young woman and, flattered to be chosen over her beautiful companion, begins an affair with the captain and soon finds herself the captive of the demonical prophet.

Written and published at the outbreak of World War II, The Carrington Incident, is a staggering forecast of the events in Germany that were already in motion and about to stun the world.