This horror oddity tells the story of a well-networked throng of devil-worshipers populating a small Arizona town who possess a strange crystal icon which houses the captive souls of their sacrificial victims. The coven, led by the thick-browed Jonathan Corbis (Ernest Borgnine), are also determined to get their hands on a diabolical "Book of Names" which contains the identities of those victims. After the family of Tom Preston (Tom Skeritt) are murdered by the coven for concealing the book, Tom sets out to avenge them. During an outrageous climax -- in which none other than William Shatner is offered up in sacrifice and Borgnine is transformed by a lightning bolt into a chunky horned demon -- the receptacle of souls is shattered, releasing the title storm and causing the congregation to melt into puddles of multicolored goo (a scene which seems to last forever). Produced in 1975 but released two years later, this film touted John Travolta's name at the height of his popularity, though his role is remarkably small (he does melt nicely at the end, however).
by Cavett Binion synopsis