When a rich countess is murdered, her bayside estate becomes the subject of a violent inheritance battle involving her husband, her illegitimate son, a real estate agent and his lover. Throw into the mix a group of nubile partying teenagers, a suspicious entomologist, a murderer slowly picking everyone off one by one and a series of outlandish plot twists and reveals, and you have one of the great films by giallo master Mario Bava, a gleefully gory delight which proved hugely influential on the slasher film cycle which emerged shortly after its release. (JB)