Mostly one shot but unless you can get a camera to go through glass without breaking it does get cuts. Note the comes and goes from the "old surgery room". I am sure if you look closer other scenes without people on them were bridge for other cuts but it does give you the ilusion of one single shot. If you are more patient than I you may time the "timer" on the wall and see if it matches the actual time gap. In summary, so much potential for a great end but the story very much dissapointed me.

After reading the reviews, I put this film on. I found myself hanging on in hope that it improved. It doesn't.

Just don't make the same mistake... Lots of repetitive shouting is about all I can say about it.

As the movie opens Claudia, a handsome fortyish woman is sitting at a sidewalk cafe having a drink and texting her prospective date Luis, a doctor she contacted through the social media. Luis repeatedly announces he will be late and finally doesn't show up. Claudia leaves the bar and is shortly after seen unconscious on the entrance steps of a hospital. She is admitted with symptoms that may indicate excessive alcohol consumption or something worse. She is attended to by the head nurse of the night shift, Romina, who brings her back from her faint and later loses track of her. The rest of the action is within the limits of the hospital and its entrance.

The movie has been shot in one single take, no cuts, so that everything happens in real time. We are invisible witnesses to the action in the hospital and.what we see (or hear from snatches of conversation, or guess from gestures) is what we get. For most of the time we follow Romina in her wanderings through the labyrinthine, dimly lit corridors of the hospital that has a dark, temporarily unused wing under repair. We are shown Romina's increasingly tense exchanges with other hospital personnel. At the end, an unexpected discovery clarifies some of the happenings, but, as in real life, loose ends remain and we are left to imagine how the remaining facts can be connected.

I found this movie endlessly fascinating and edge/of/you/seat suspenseful. The no cuts format is not a gimmick; it produces a thrilling sense of immediacy to the action. Acting is first rate, especially from Laura Novoa (Romina) who is on screen most of the time. She conveys to perfection her increasing bewilderment (even the neatness of her hairdo is gradually lost). Direction is fluid, music supports the action unobtrusively and the script is perfectly adapted to the tale. The director is identified under the pseudonym "Who", and a little Web search reveals him to be Marcelo Politano, who appears with his own name in the credits as producer and as one of the script writers. Besides Causality, Politano has two movie credits; Soy Tu Karma (I am your Karma, 2017) and Esencial (Essential, 2021). I have not seen either but on the basis of this film I will be waiting for more of his work.