The Woman In The Window ending explained - the killer reveal and exactly what happened

Adams stars as Anna, a therapist suffering from agoraphobia who is unable to leave her New York City town house. She spends her time watching old movies (including Rear Window, which this clearly borrows from), chatting to her estranged husband Ed (Mackie) and daughter Olivia on the phone and watching her neighbours across the street, including the newly moved in Russell family.

Anna meets the Russells’ 15-year-old son, Ethan (Fred Hechinger) and later his mother Jane (Moore), but then she later witnesses Jane being stabbed to death from her window. However, when the police call, it turns out that Anna must have been mistaken, as Alistair Russell (Oldman) produces his wife Jane and she looks nothing like the woman she met (and a lot like Jennifer Jason Leigh).

Did Anna – who is on a cocktail of medication for her agoraphobia, and is mixing the pills with alcohol – imagine the murder? Who was the woman she met and did Alistair kill her? Or should she be suspicious of her slightly shifty downstairs tenant, David (Russell), especially as she found one of Original Jane’s earrings on his bedside table?

Twist 1: It's not Jane

As the plot gets more and more implausible, just who did what to whom and when becomes more clear.

It turns out that Anna’s psychiatrist Dr Landy (played by Tracy Letts, who also wrote the screenplay) is, quite frankly, a disgrace to the profession, as he knowingly prescribed drugs to Anna that could cause her to hallucinate, and didn’t seem overly bothered that he left a clearly unstable woman to fend for herself home alone with only David and her pet cat for company.

And Anna has definitely been hallucinating – when everyone including the police assembles in her house and she starts accusing Alistair of murder and David of being generally slippery, it is revealed that the cause of Anna’s agoraphobia was the death of her husband and daughter in a car accident that she was responsible for. All the phone conversations she had with them earlier in the movie were taking place in her imagination, so the police surmise that she imagined Original Jane and the murder, too.

She finally accepts the truth, and when she is once again home alone, Anna films a last will and testament video on her phone, crushes some pills ready to kill herself, and waits for David (who has understandably decided to move out) to come and collect the last of his things.

Who is Katie?

While waiting, she scrolls through old photos on her phone and comes across one she took of her cat (the true star of the movie, by the way) – and there is Original Jane’s face, reflected in a wine glass. Anna shows the photo to David and he identifies the woman – her real name is Katie and he had a one-night stand with her in Anna’s basement. Katie revealed to him that she was Ethan’s real mother, a former drug addict who had tracked the Russell family down so she could see him.

Unfortunately, David decides not to go to the police with Anna and starts to leave – only to be bashed in the head by Ethan who has been lurking in the shadows.

So wait who killed Katie?

It turns out that Ethan is a teenage serial killer (who has been hiding out in Anna’s house while his parents think he is at camp, and inexplicably got her keys so he could come and go in creepy fashion) and he reveals to Anna that he killed Katie after discovering she slept with David. For some unexplained reason he also previously killed his father’s secretary, Pam, by throwing her out of a window – a crime that Anna had been convinced Alistair was guilty of, and the reason the family had relocated from Boston to New York.

It now looks like it is Anna’s turn to be killed. After she utters a monologue about not wanting to be in a world with people like Ethan in it, she goes to swallow her crushed up pills, but instead hits him with her wine bottle and flees the room. David, who isn’t quite dead yet, tries to grab Ethan to stop him chasing her, but Ethan stabs him (well, David’s dead now) and goes after Anna.

While anyone else would go downstairs to the front door, Anna heads up to the roof of the house with Ethan in hot pursuit. They struggle out on the roof in the pouring rain, with Ethan plunging a gardening fork into Anna’s face and then trying to drown her in the deep rain puddles (the roof clearly has a drainage problem).

She fights back and pushes him onto the glass roof skylight – which David had earlier told her needed fixing if you missed that piece of thudding foreshadowing – and Ethan smashes through it and falls to his death.

Wait, Anna survives?

Anna wakes up in hospital to see kindly police officer Detective Little (Bryan Tyree Henry), who returns her phone and advises her to delete the video she made when she was considering suicide. He also tells her that Katie's body has been found, and while Alistair – who must have been covering up for his murderous son, including hiding the body – isn’t saying much, his wife Jane is co-operating with police.

The movie then jumps to nine months later. The Russell home is empty and up for auction, and Anna is moving away. She takes one last look at her late daughter’s empty room, leaves the house and gets into a taxi – with her cat, thank goodness – and drives away.

The Woman in the Window is streaming now on Netflix.

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