Director Oriol Paulo delivers an exceptional psychological thriller set in a 1970s asylum that keeps you constantly guessing whether protagonist Alice is a brilliant private investigator trapped in a conspiracy or a masterfully manipulative patient in her own delusion. Bárbara Lennie carries the entire film with commanding charisma, alongside Eduard Fernández as the stoic hospital director. With its fantastic production design and tense score, this layered puzzle box of a film makes every minute engaging and stands as essential viewing for fans of cerebral mystery thrillers.

"Alice" (Bárbara Lennie) is a private investigator trying to get to the bottom of what she thinks might have been a murder in a prestigious sanatorium. She concludes that the best way to do that is to feign being worthy of admission but once she is through the large metal gates of this establishment, she soon realises that it's boss "Dr. Alvar" (Eduard Fernández) is not a man to be crossed. That's going to make her investigation quite difficult, especially once she realises that she can glean little from the heavily drugged patients nor from the loyal team of medical professionals who run the place. Running in parallel to her detective work, we learn of another fatality at the institution and so now "Alice" has to conclude if these events might be connected - all against an increasingly perilous background for herself as it appears that perhaps "Alvar" is aware that she isn't all she claims to be. There isn't really any need for this film to go on for quite so long, indeed if it condensed the last hour into half of that time, it would greatly increase the accruing sense of complicated menace that auteur Oriol Paulo has crafted here. There are twists and turns galore as the plot thickens and by half way through, the questions of just how we measure who is sane and who is not are posing a real puzzle for us watching. Is "Alice" all we think she is, or is there something altogether more complex being played out here? There are clues and counter-clues, and even by the end it's by no means predictable what might play out and who the enigmatic "Dr. Donadio" is. Simultaneously, this also presents us with quite an authentic critique of how this particular Cuckoo's Nest functions and at how automated and medicated the lives of so many of the inmates have become. Is this treatment or is this merely incarceration by another name? Lennie holds this together really quite effectively but it's Fernández who exuded the more compellingly manipulative degree of menace that kept me guessing right until the last few scenes... Perhaps make a directory's cut that's shorter? In any case, if you like your thrillers heavy on the psychology, then you'll enjoy this.