The acting is annoying, at least in the flashback sections. Vincent Price is Vincent Price, I don't mind his acting, but all the others are pretty bad. For example when the kid says "mommy where are you?" and the mother sits there ignoring the kid, not even trying in any way to comfort her daughter.
Also, the film is boring, there are a few good scenes, but that's all.

Fairly slow moving and campy. Price brings some amount of foreboding and charisma to the role but seems hardly enough to make the film memorable.

Pretty effective chiller for its time, I'd say. The twist in the the second half puts some deeper issues into the story that barely get touched (the ending takes place in a church). You be the judge.