On the eve of her wedding, the beautiful opera singer Malvina is mysteriously abducted by a malevolent Dr Droz. Felisberto, an innocent piano tuner, is summoned to Droz’s secluded villa to service his strange musical automatons. Little by little Felisberto learns of the doctor’s plans to stage a “diabolical opera” and of Malvina’s fate. He secretly conspires to rescue her, only to become trapped himself in the web of Droz’s perverse universe…