After a mysterious trunk arrives at a prestigious girl's boarding school, its staff and students - including an orphaned heiress and an amateur sleuth - are targeted by a shadowy murderer.

The corpses are piling up at St. Hilda's School for Girls, leaving top cop Michael Rennie with more than the usual suspects. Is the killer Mark Damon? Peeping Tom Luciano Pigozzi? Or someone else? Mario Bava's original script "Cry Nightmare" was entrusted to director Antonio Margheriti. Be sure to see the Italian version which runs 98 mins. (the film was hacked by 15 minutes and retitled by American International Pictures to show mainly at drive-ins).—Monty Britton