British bank cashier Eldred Caldwell lives with his wife on the edge of the Arabian desert. One day a man named Richard Manners appears at their doorstep. He has some incriminating information about Eldred, who is so devastated he disappears, an apparent suicide. His wife flees into the desert, with Manners in hot pursuit. She is taken in by an unlikely rescuer and years later, after she becomes a nurse when World War I ends, she makes a startling discovery.
