Sundance: Alison Brie struggles against aliens and her own mind in 'Horse Girl'

Cinema has a long history of exploring the question of whether what we dismiss as madness is actually closer to the truth than the world we believe in, and director Jeff Baena's Horse Girl adds another chapter to that storytelling tradition with an examination of one woman's suspicions that she's being secretly cloned by aliens.

Baena (Life After Beth, The Little Hours) co-wrote the screenplay with Alison Brie (Community, The Little Hours), and he explained to the Sundance Film Festival crowd that much of the inspiration for the film came from Brie's pitch to him about her own family history.

"She asked if I wanted to go on a hike with her — she lives right in my neighborhood — and she had an idea. Her grandmother had paranoid schizophrenia, and a lot of the stuff that she's talking about the movie was actually taken from her real life," he said. "So she's sort of pitching me this idea, and then I had another idea that had something to do with, like, a horse girl, and we realized these two ideas actually were kind of the same idea, so we just kind of married them together and just started working on it right away on that hike."

Baena invested some of his personal history into the story as well. "I've always been interested in alien abduction for years. I've always been fascinated by it, and I actually had some pretty vivid dreams that involve aliens and, not to get super weird, but I feel like I've seen some UFOs. Yeah, so it's something of personal interest to me."

Brie stars as Sarah, a quiet, awkward, even banal woman who works in a craft shop with Joan (Molly Shannon) and spends her nights watching Purgatory, a supernatural procedural show starring Matthew Gray Gubler (Criminal Minds) and Robin Tunney (The Mentalist). When she starts having strange dreams about alien abductions and experiencing unsettling time loss and dangerous somnambulistic displacement, she begins to suspect an otherworldly conspiracy unfolding around her and her dark family history.

The ambiguity between what's real and what's imagined was Baena's focus. "That line sort of was the movie. That was the intention at the inception of the movie, to always walk that line, keep it as something subjective and see everything from her eyes and experience things as she's experiencing them, without judgment. Whatever follows, we will be invested in it because we're invested in her character. So whether or not we judge it to be real or not, it's real for her."

"If you're having experiences that seem supernatural or out of the ordinary, you know, general consensus is that's not possible, but you feel like it's real," he added. "That kind of thing doesn't really jive with society, so I just wanted to kind of explore what the fallout from that was."

Horse Girl is now playing at the Sundance Film Festival, and will be available on Netflix on February 7.