This was an excellent suspense film with outstanding cinematography and interesting characters played by a strong cast.
There are lots of complimentary adjectives in the above sentence but the film deserves it, particularly the photography (see this on DVD). The lighting is as good as anything I've ever seen in film noir (this is not a film noir, as one reviewer correctly points out). In fact, outside of David Lean's "Oliver Twist, " this may be the best-looking black-and-white film I've seen. A good part of the visual treat is viewing the fantastic Victorian house where most of the action takes place.
The lead character, played beautifully by Dorothy McGuire, is one the viewer cares about which helps get one involved in the story. All the other characters are fun to watch, and are detailed here in other reviews. I go along with most in saying Ethel Barrymore was the most likable.
There are a few holes in the storyline, to be sure, but one doesn't care since the film movies rapidly, the story keeps you so involved and the visuals and audio are so interesting. This latter also features the longest thunderstorm on record!