The young woman, named Jane, begins to experience strange occurrences in her new apartment shortly after moving in. She hears odd noises, encounters swarms of flies and rats, and finds dead animals seemingly placed purposefully around her apartment. As she tries to uncover the source of these bizarre happenings, she finds that her neighbors all have their own distinct quirks and secrets.
Her upstairs neighbor, Greg, is a reclusive artist who takes an interest in Jane and tries to help her solve the mystery. He also warns her to stay away from the old woman who lives below her. Jane also begins to suspect that her boyfriend, played by actor Austin Pendleton, may be involved in the strange occurrences, as he seems overly possessive and unwilling to let her go.
As the tension and paranoia in the apartment building escalates, Jane's life is put in danger and she must discover the truth before it's too late. The film builds towards a twist ending that reveals the shocking truth about the apartment building and Jane's connection to it.
Starring Juliette Lewis as Jane and William Hurt as her upstairs neighbor Greg, The 4th Floor is a psychological thriller that plays with themes of isolation, trust, and desperation. Directed by Josh Klausner, the film keeps audiences guessing until the final minutes.