Behind its forbidden doors an evil secret hides! The dead are restless at Horror House when a group of swinging Londoners and their American friend hold a séance in an old fright-filled mansion. But their thrills turn to terror when they start to get gruesomely picked off one-by-one. Frankie Avalon and Jill Haworth star in this eerie proto-slasher helmed by Mark of the Devil director Michael Armstrong.
