You’ve likely encountered the storyline before, or at least elements of it, in other movies. Julia (Laura Regan), pursuing a master's degree in psychology, finds her life disrupted when a former friend, Billy (Jon Abrahams), reaches out to her, speaks at length in a confused manner, and then takes his own life in front of her. The audience has already witnessed Billy’s childhood experiences—being seized by unseen entities during the night—suggesting he carried deep-seated issues that even Julia couldn't resolve. At Billy's funeral, Julia connects with his other friends, Sam (Ethan Embry) and Terry (Dagmara Dominczyk). These friends share a history of frightening nightmares from their childhoods, now marked by unusual symbols on their bodies that seem to be an invitation for mysterious, computer-generated beings. Seeking answers, Julia consults Dr. Booth (Jay Brazeau), a former psychiatrist, who attempts to provide psychological insight. Julia’s boyfriend, Paul (Marc Blucas), seems unable to fully grasp the situation either; frankly, I didn't entirely understand it myself. The fundamental problem with "They" lies in its poor handling of an otherwise interesting concept. The idea of childhood monsters returning to haunt adults holds potential, but the script lacked essential explanations—the origin of the creatures, the reason for selecting specific victims, and so on. This is a significant shortcoming given how unengaging the film already feels. While the cast performs adequately, portraying fear at appropriate moments, the musical score is disappointing; it sounds like background music from "The Music Man." Director Harmon’s abilities are squandered by the weak screenplay—he clearly needs a better script to showcase his talents. The movie borrows heavily from other films such as "Jacob's Ladder," "Phantasm," the remake of "The Blob," and "The Sixth Sense," even blatantly copying the pool scene from "Cat People." Although the DVD includes an alternate ending, which is reminiscent of "The Cabinet of Dr. Caligari," it’s actually preferable to the version that appears in the final film. The monsters' special effects are mostly kept hidden, revealing them to resemble giant bats. They do manage a few startling moments, but these are insufficient to compensate for the nonsensical plot. Eventually, you realize much of the visual work involves someone simply switching lights on and off. "They" possessed a promising director, a capable cast, and a modest budget; what it didn't have was a script that deserved to be made into a movie.

Source on TMDB