Mr. DuLac’s review published on Letterboxd:
What if she wasn't alone?
Far superior to anything that I expected. Almost a throwback to giallo films. It doesn't rest on just one idea as each act of the film is distinctively different. The story might be about a woman attempting to solve the mystery surrounding her sister's suicide, but it evolves beyond that a great deal.
One of the things I liked most was that the entire third act feels like a 45 minute climax. Things feel like they're ramping up towards the end and you're just slightly passed the halfway point of the movie. Loved the "cat and mouse" chase here. There's a certain style decided upon during those moments too that I thought was just great, but can't comment on without going into spoilers. It has to do with faces.
First time seeing Belén Rueda in a film and I gotta say I loved her in this. Great central performance.
My one gripe might be that the very last closing moments of the film weren't my cup of tea. Thought it was a bit much and could have benefited from "less" if that makes any sense.