Legendary horror director Mario Bava did not want to make this standard thriller, and it certainly bears the lackadaisical mark of a contractual-obligation film. The plot is yet another variant on the Ten Little Indians story, with an inventor taking a group of investors to an island, where they are murdered one by one by an unseen killer. There are picturesque beach scenes and some well-composed images of bodies hanging in a meat locker, but it has all been done before, and better. The visuals are stylish and the production design is sleek, but the familiar storyline drags and the film never reaches the delirious frenzy of such Bava classics as Antefatto despite the best efforts of a cast including Edwige Fenech, Renato Rossini, and William Berger.
by Robert Firsching synopsis