Sisters is an oddball for sure, but a well-constructed film that showcases the budding talent of a young Brian De Palma just four years before Carrie. Half erotic thriller and half psychological nightmare, Sisters is told from multiple perspectives to provide a fully developed scenario in which the true killer may not even exist. The way I read into it, there are several explanations for who is behind the murders, and all of them are completely insane. Margot Kidder and Jennifer Salt deliver powerhouse performances in this trippy thriller.
After meeting on a bizarre hidden camera show, French-Canadian model Danielle (Kidder) and her beau-to-be Phillip (Wilson) hook up at her place. The next morning, Phillip is stabbed to death by Danielle, and it's witnessed by Grace (Salt), who lives across the street. Grace is a small-time journalist looking to move up in the world, and she calls the cops. Meanwhile, Danielle and her husband/doctor Emile (Finley) have already cleaned up the scene. Now, Grace makes it her mission to prove what she saw, and the investigation leads her down a crazy rabbit hole involving conjoined twins, conspiracy, and multiple personalities. The final act takes a hard left into a confusing dream sequence, but the ending is so bleak and off-kilter that you can't help but appreciate the thought.
Sisters challenges a lot of erotic thriller tropes, keeping you in suspense the whole time, even though you know who did it from the get-go. What you don't know is why. De Palma has always been an underappreciated director who knew how to give an audience something they'd never seen before. Even in his early work, that's exactly what he did with Sisters.