Haunting is right; the atmosphere takes hold from the very first shot of the dreadful Hill House against an angry sky. The interiors are deliciously gothic and there are plenty of spooky bumps in the night. What really cemented the film's greatness though is the depth of characters. Each is unique and engaging, carving out their own personalities and relationships with each other. I was very impressed with the subtle indication of lesbianism in a film of its age, and the attention to each characters' flaws. Fantastic cast all around and compelling interactions.

The actual haunting aspect is pretty tame most of the time, and the film sags a little bit in that there isn't much "investigating" going on, compared to films like the similar Legend of Hell House. They're basically just hanging out in the house, waiting for the ghosts to come to them (which, luckily enough, they do). A few really good scenes, coupled with the smart character writing is what holds everything together.