A lot of people get it wrong. The key character isn’t who you think it is. I could suspend 1/3 of my disbelief. It’s a sexual trauma trigger for sure. Be warned. Spoilers ahead.
The sister, Olivia, or whatever, is the main character. She, traumatized herself, was, is, and continues to lie and deny her sisters trauma. No, not just the initial traumas as a child. But also the present day encounter. Why are so many viewers/reviewers easy to believe the sister when she says Peter’s character wasn’t the perpetrator in high school, when she’s denied and lied about her sisters actual trauma since she was 8? Your radar is so much weaker than you think it is.
Peters character IS the perpetrator.
He later married a woman who looked just like his victim (baby Sylvia) when he was a teenager and somehow ended up with that same person decades later. He’s not mistaking Chastains character for his dead wife like other reviewers write. it’s his wife who is the Chastain lookalike. his guilt is suggested 1) when he stands in the hallway looking at the two doors, 2) the abusive “yes come in” to Sylvias daughter when he’s naked in her room, 3) the hand on her thigh 1.5 times when she’s alone with him in his house in the end of the film and the caretaker goes upstairs, 4) why he followed Sylvia home in the first place 5) why he can start having sex with Sylvia in the tub with the daughter in the next room 6) The sister continues to defend her actions even when he niece confronts her proving she will still lie. 7) the sister Olivia walks away avoiding eye contact as she’s talking when she tells Sylvia that Peter’s character wasn’t enrolled in her school at the time.
And because, as her own daughter says, Sylvia never shares anything with her, the daughter never learns to listen to herself or speak up, only thinks in theory that she would speak up (regarding that naked bedroom scene). That’s how trauma works. The daughter also knows she’s uncomfortable with Peter’s character and stays away by sleeping at her aunt and friends place the first couple nights he’s at their apartment but her perception of him is colored by other positive events and that get buried.
Didn’t believe:
A New Yorker woman walking home and not turning around to look behind her, oh please.
I don’t think Peter’s character having dementia and ability to consent is an intentional theme here. But if it was, it adds another instance of the same issue, that the traumatized Sylvia can’t discern it’s an issue because she’s traumatized herself in the act, her dissociation clearly shown in their first time at her house in her bedroom.