Dark Season (1991)

Dark Season centres around a normal English school, but all is not what it seems... For the machinations of the mysterious Mr Eldritch are at work. A shades-wearing, bleached-blonde millionaire, he arrives at the school claiming to be its benefactor; donating computers to every student. Investigating Eldritch is the ever-inquisitive, wise beyond her years third former Marcie, who with her fifth form friends, Reet and Thom, uncovers a plot to that doesn't just threaten the pupils of the school, but the whole human race!