A new featurette for Smile takes us behind the scenes of the creepy horror movie from director Parker Finn. The upcoming film marks Finn’s feature debut and is adapted from his acclaimed short film Laura Hasn't Slept.

Smile follows Dr. Rose Cotter (Sosie Bacon), a psychiatrist who witnesses the gruesome suicide of a young woman who claims to see an entity that smiles at her from the shadows. After the traumatic event, Dr. Rose starts to experience hallucinations herself, which leads her to investigate the multiple occurrences of people who killed themselves after describing a similar apparition. It’s a simple but effective concept that leads Dr. Rose on a race against the clock to figure out where this menace comes from and how she can survive it. In the new featurette, Finn underlines how Smile was filmed to give the audience a constant sense of “unease,” as it deals with psychological horrors that are just as deadly as material ones.

While talking about his creative process, Finn says he wanted “to create a film that feels like an escalating nightmare”, and that happens because “the evil in the film uses a smile as a mask to hide its true intentions.” As such, instead of revealing the true horrors that Dr. Rose is facing right from the start, Smile slowly builds up the tension by becoming scarier through its runtime. It does sound like the perfect way to start the spooky season in the right mood.

Caitlin Stasey smiling creepily at the camera in 'Smile.'

RELATED: 'Smile': Release Date, Trailer, Cast, and Everything We Know So Far

Finn’s Laura Hasn't Slept won the SXSW Film Festival's special jury recognition Midnight Award, an award that helped the director to get the funding needed to turn his short into a feature. The short starred Caitlin Stasey, who’s also set to return for Smile. The cast for Smile also includes Kyle Gallner (A Nightmare on Elm Street), Jessie T. Usher (Dangerous Lies), Robin Weigert (The Undying), Kal Penn (The Sisterhood of Night), and Rob Morgan (The Unforgivable).

Smile is produced by Marty Bowen, Wyck Godfrey, Isaac Klausner, and Robert Salerno. Adam Fishbach acts as executive producer.

Smile hits theaters on September 30. Check out the new featurette and the film’s synopsis below.

After witnessing a bizarre, traumatic incident involving a patient, Dr. Rose Cotter (Sosie Bacon) starts experiencing frightening occurrences that she can't explain. As an overwhelming terror begins taking over her life, Rose must confront her troubling past in order to survive and escape her horrifying new reality.