I left the screening of “Horse Girl” with a deep dissatisfaction, a film that is an odd misstep from director Jeff Baena (“Life After Beth,” “Joshy”). The first half of the film is awkwardly charming, but then it becomes something completely different in the worst possible way. The goodwill earned from the oddball sensibility of the story is derailed when things go in a completely “WTF?!” direction. This is a dark movie that gets weird for no good reason, and it feels like the project becomes a victim of writers (Baena and Alison Brie) who can’t figure out the ending to their story so they take the weird route. It’s lazy, sloppy, and super disappointing.

The goofy and sweet Sarah (Brie) has a quiet and fairly simple life. She spends her days working at a crafts store, her afternoons visiting an equestrian center, and her evenings in from of the t.v. watching her favorite supernatural crime show. When her coworker Joan (Molly Shannon) gives her a DNA testing kit for her birthday, it sparks a curiosity about her family history that leads to a pattern of sleepwalking episodes and disturbing dreams. These visions begin to seep into her daily reality, making the fine line Sarah walks between what’s real and what’s fake even more blurred. Is she a clone? Is it the work of extraterrestrials? Or is her family history of paranoid schizophrenia finally starting to affect her?

The mystery aspects of the story are interesting, and Baena treats his characters with tenderness and respect. The film is at its best when it presents as a quirky character study and its worst when it becomes too abstract. It isn’t the serious and depressing plot points that ruin the film, but it’s the outlandish finale that honestly makes no sense whatsoever. The ending feels like a slap in the face to those dealing with mental illness as much as it does to the audience.