While the cinematography feels a bit dated for the late 1970's, the pacing of the film is good and the tension keeps increasing until it hits a fevered pitch toward the end of the film. Furthermore, there's a small surprise in the climactic moments of The Spell that works very well.
While The Spell is not in the same league as other late 70's classics such as Carrie and Fright Night, it's surprisingly good and I was thoroughly entertained by it. Don't miss this one. It's a neglected gem of late 70's TV horror. [You can stream this one on Netflix.]
RATING: Very Good.
For more info check out the film's entry in IMDB.