The plot focuses in on Elizabeth who after finding her sister hanging as the result of an apparent suicide. Not convinced of the police reaction and findings of the case Elizabeth joins the "Salem Academy" which her sister attended previously to find answers. Upon further investigation Elizabeth and their friends uncover tales of historical "Witch Hangings" and other mysterious goings on in the underbelly of the school, leading to the discovery of a satanic cult under there.
While not being a hugely gripping watch, or a huge budget feature (I believe it was made for TV) its something to do and worth watching once, and beats watching most shows on television.
Interesting note, the film was remade in 2000 and starring Shannon Doherty and to be honest I find this a much easier watch. Not in the least part because I think miss Doherty is a babe. Tho not directed by Spelling it does have a very 90210 / The Craft type feel to it but that just depends on your tastes I guess. The two movies do have a fair amount of differences in the plot so there's probably no point going into too much detail about both films but they follow a central thread as outlined above.
Overall I think the 2000 remake of this one is a more entertaining watch so if you're going to watch only one I'd personally choose the remake but I've listed both of them below which are available for streaming from youtube
the 1973 version:
and the 2000 version:
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