I would like to start this review with a hearty "This Movie is Not For Everyone."
The truth is I believe it takes a specific kind of person, with a specific set of life experiences, to click with a movie like this. When I was Casey's age, I felt supremely isolated from everyone and everything in my life, filling the void with horror, and ARGs. This movie felt like holding a mirror up to that lonely part of my life, having this yawning void in your chest, unable to be fully filled, staying up the latest hours of the night trying to scare feelings into yourself.
The reverence that this film takes from its inspirations is honestly refreshing, referencing several ARGs I vividly remember, and including multiple ARG community alumni. This movie does not feel like a soulless cashgrab, unlike the likes of 2015's Always Watching, or 2018's Slender Man. Part of this, I feel, is that it tells its own story, not one of supernatural thrills, but one of coming of age while lonely, and mental illness intersecting with that.
It would have been so easy for the message of this film to be "ARGs Bad," but it takes a more nuanced approach, where the bad is Casey's agency being taken from her. It would be hard to recommend this to everyone, but for those who think it would hit home from this review, I recommend it to the ends of the earth.