Roger Spottiswoode, vet editor who co-authored a respected book on the subject with Karel Reisz, makes a competent directing debut here.As in Jamie Lee Curtis’ other shocker pix, she limns the feisty survivor character in a group of young people menaced by a psychotic while having a wild party on a train. Her acting fits a narrow groove. But it must be said in young thesp’s favor that she has not been given the most challenging material. Efficient screenplay quickly sets up the premise by showing a repulsive sick joke being perpetrated by college med students on a sensitive youth who goes insane as a result. Three years later the kids all take a train excursion to celebrate their graduation, and the chickens come home to roost.