You Shall Not Sleep Tonight is a psychological horror that blends supernatural terror with a deeply unsettling premise centered around sleep deprivation. The film follows a group of medical volunteers participating in an experimental sleep study designed to push the limits of human endurance. What starts as a clinical investigation quickly devolves into a horrifying nightmare.

The main character, Emily, a med student with a traumatic past involving her mother’s mental illness, signs up for the experiment in the hopes of earning extra credit and financial compensation. Alongside her are other participants, each with their reasons for joining, including a soldier suffering from PTSD, a mother of two trying to manage her insomnia, and a tech genius who wants to prove sleep is unnecessary.

The study’s premise is simple: the participants must stay awake for seven consecutive days under observation. But as the hours pass, the sleep deprivation begins to play tricks on their minds. Hallucinations, paranoia, and violent mood swings emerge, blurring the line between reality and delusion. The film excels at building a suffocating atmosphere, with the camera work mirroring the characters’ deteriorating mental states.

Things take a dark turn when the participants begin seeing a shadowy figure lurking in the corners of the sleep lab. At first, they believe it’s another hallucination, a product of their exhausted minds. But soon, they discover that the figure, known as “The Sleepless Man,” is an ancient entity that preys on those who push the boundaries of sleep too far. He feeds on their fear and slowly drives them to madness, turning the lab into a death trap.

As the participants try to escape, they realize that the lab was never meant to help them—it’s a front for something far more sinister. The Sleepless Man is not just an apparition but a force that can manipulate time and space, trapping them in an endless waking nightmare. Emily must confront both her past and the entity itself in a race against time, with no guarantee of survival.