A doctor becomes involved with a woman who is married to a man who is up to something suspicious.
Title check: The title is from a poem that is quoted in the movie; it sounds good, but I don't think it really gives a good sense of the movie.
The movie starts out strong, with some moody shots of a train during a storm, and a passenger on the train meeting a woman who seems to be scared about something but covering it up. Unfortunately, the movie gets bogged down somewhat after this by some overlong sequences of character development and exposition; fortunately, it picked up again before I lost interest completely. It's only marginally a horror movie (madness plays a role in the proceedings), and I've often heard it described as a variation on GASLIGHT; quite frankly, I was quite pleased to find out that, though it has certain plot elements that bear a similarity to that movie, it really is playing a somewhat different game. Not bad, but the first half does require an extra dose of patience.