The ultimate Sundance horror film (for better and for worse), Master simmers along like the heir to Get Out for well over an hour, then takes some inane turns in the home stretch that will leave viewers scratching their heads — and not in a good way.

Until then, writer/director Mariama Diallo’s feature debut thrillingly blends supernatural suspense with social commentary via the dual storylines of freshman Jasmine (Zoe Renee) adjusting to life at the overwhelmingly white Ancaster College outside of Boston, and Dr. Gail Bishop (Regina Hall) experiencing her own growing pains as the school’s first Black professor to hold the titular position — a kind of hybrid teacher/Dean of Students role.

Whether in Jasmine’s allegedly cursed dorm room or Gail’s bizarrely infested on-campus housing, there’s a tantalizing sense of foul play both otherworldly (Ancaster has ties to the Salem Witch Trials) and human. Neither’s presence is exactly embraced by the student body, faculty or staff, which seem jointly invested in making Jasmine’s life miserable, and though Gail’s colleagues (including one played by Bruce Altman) at least abide her involvement for the sake of optics, something’s not quite right with this group of academics. 

As the two women attempt to power through their troubles, Renee and Hall prove reliable co-leads as the line between dreams and reality become blurred, occasionally to the extent where it seems even Diallo isn’t sure of the boundaries. The ambiguity raises all sorts of fascinating theories regarding precisely what is happening, yet it’s undercut by Master’s status as yet another film where the protagonists experiencing psychological torment mysteriously shrug it off without seeking help, allowing for a series of escalating but diluted traumas until a breaking point is eventually reached.

Once someone indeed snaps, so does the film’s hold over the audience. Suddenly, characters make abrupt decisions that clash with previous approaches and jeopardize their safety through gullibility, particularly an 11th-hour “revelation” regarding the college’s other Black professor, Dr. Liv Beckman (Amber Gray, The Underground Railroad).

In its race to the finish line, Master flirts with becoming a different and far lesser movie entirely, and ends on a decidedly mixed note. But while Diallo may not currently know how to stick the landing on a feature-length project, there’s enough promise in her first foray of this magnitude to suggest that she will soon.

Grade: B-minus. Rated R. Starts March 18 at Grail Moviehouse, when it will also be available via Amazon Prime Video

(Photo: Amazon Studios)