A Bay of Blood (Italian: Ecologia del delitto; also known as Twitch of the Death Nerve, Blood Bath and Reazione a catena), is a 1971 Italian horror film directed by Mario Bava. Bava co-wrote the screenplay with Giuseppe Zaccariello, Filippo Ottoni and Sergio Canevari, with story credit given to Dardano Sacchetti and Franco Barberi. The film stars Claudine Auger, Luigi Pistilli and Laura Betti. The late Carlo Rambaldi created the gruesome special make-up effects. The story details the simultaneous murderous activities of several different characters as they each attempt to remove any human obstacles that stand in the way of an inheritance of a bay.