AllMovie

Elderly, avaricious Countess Ferenzi (Iphigenie Castiglioni), whose fascination with her priceless four-strand pearl necklace borders on the obsessive, inexplicably chokes to death--as her maid Nina stands by passively, refusing to call the doctor. Shortly thereafter, Nina herself is found strangled, whereupon suspicion falls upon the late Countess' butler Michael Barry (Sean McClory). But the mystery will not be solved until Barry gives his girlfriend Grace (Jan Miner) a valuable present...a four-strand pearl necklace.