Sisters (also known as Blood Sisters in the United Kingdom) is a 1973 American psychological horror film directed by Brian De Palma and starring Margot Kidder, Jennifer Salt and Charles Durning. The plot focuses on a French Canadian model whose separated Siamese twin is suspected of a brutal murder witnessed by a newspaper reporter in Staten Island.
Largely influenced by the films of Alfred Hitchcock, the script for the film was written by De Palma and Louisa Rose, and the score composed by Bernard Herrmann. Sisters was the first thriller for De Palma, who followed this film with other shocking, graphic thrillers.
The film was met with critical praise; Roger Ebert noted that the film was "made more or less consciously as an homage to Alfred Hitchcock", but said it "has a life of its own" and praised the performances of both Kidder and Salt. Vincent Canby of The New York Times called it " a good, substantial horror film" and stated "De Palma reveals himself here to be a first-rate director of more or less conventional material", also noting the film's references to Repulsion (1965) and Psycho (1960).