Daniel Goldhaber‘s “Cam” feels like a great, un-aired episode of Netflix’s acclaimed anthology series “Black Mirror.” Goldhaber’s film is a mysterious dive into the unknown, a dreamy and surreal take on social networking that will make you think twice about not just webcamming, but what someone’s self-worth, and their own identity, might really mean online.

Set against the backdrop of online sex work, “Cam” grips you and doesn’t let go from its very opening scene, as you are thrust into the world of young women who host sexually-explicit shows online. More specifically, Goldhaber is interested in the psyche of Alice, the intriguing lead character, whose identity, which she has meticulously built up over the years, is threatened by an outside force.

Madeline Brewer, best known as the one-eyed Ofwarren in Hulu’sThe Handmaid’s Tale,” gives an incredibly brave performance as Alice, a camgirl with the alias “Lola,” who has amassed a fairly large online fan-base. The show she puts together every night is not just meant as sexual viewing, but also as a theatrical experience. Alice’s shows consist of wardrobe changes and no shortage of shock value, such as faking her own death with a shotgun or knife. Sex and death bring the viewers in, and Alice knows she is very close at making the host site’s Top 50 Most Popular Girls list, which to her means fame and fortune.

The film takes a turn when Alice gets locked out of her webcam account, but what’s weirder, is that someone who looks exactly like her has taken over her channel, broadcasting videos in the process. Her fans can’t tell the difference and think it really is Alice. Suffice to say, she starts to lose her mind as the film sinks into a David Lynch-ian rabbit hole with details too hypnotic to reveal in this review.

Who is the imposter that has taken over Alice’s online identity? The answer is much more complicated than you might expect.

Goldhaber banks on Alice’s reactions to the peculiar events as a way to suck the viewer in. We are as clueless about what’s happening as she is, which gives the viewer a personal connection to Alice. We are in this maze-like dream with her together and demand the same answers as Alice does. The detective work that ensues is filled with efforts to find out what two of her most ardent fans might know about the unusual switcheroo, which leads to notoriously devious circumstances.

“Cam” isn’t a horror movie as much as it is a story about how we try to control our online identities. The world of webcamming is presented to us in refreshing ways. It’s no surprise that “Cam” was written by Isa Mazzei, a former camgirl herself, who infuses everything she might know about the industry of voyeurism into her intricately designed screenplay. The attention to detail makes the film not only a first-rate thriller but an indelible portrait of the behind-the-scenes preparations one has to make, the technical maneuverings, and even the friendships and rivalries that build up between various camgirls.

Director Goldhaber, making an excellent feature directing debut, shows an impressively assured hand at filmmaking, especially as Alice’s mental state starts to blur the lines between reality and fiction. The highly stylized images, and the way reality and dream are shot in the exact same way, is stunningly rendered through cinematographer Katelin Arizmendi’s colorfully acerbic lenses.

Brewer, of course, is the glue that holds the puzzle together. If we didn’t care for her surreal plight, then the film would just not work, but the actress builds a thoroughly believable character in Alice. She has a sort of single-mindedness which recalls Naomi Watts‘ Betty in “Mulholland Drive,” another film which explored identity switches. Just like that film, “Cam” feels like a nightmare that won’t let go. [B+]