Written and directed by Scott Beck and Bryan Woods, this is less of a horror film and more of a psychological thriller.
When two Mormon missionaries, Sister Barnes (Sophie Thatcher) and Sister Paxton (Chloe East) knock on the wrong door, they become locked in a religious battle of cat and mouse with the ultimate heretic, Mr. Reed, played wonderfully against type by Hugh Grant.
Mr. Grant is charming, yet gonzo in his theological ideas. With just ever so slight facial movement, he can convey twisted menace at any given moment while playing the friendly host to the two young women. He challenges their beliefs and goes on and on about the one true religion, while giving them history lessons about various organized religion. He tells them they are free to leave but offers little in the way of freedom, except through a choice of doors marked "Belief" and "Disbelief".
The film is never really scary but does build a reasonable amount of suspense and creepiness as it goes on. Introducing a "prophet" later in the film, who Mr. Reed tells the two women can be resurrected, is the closest the film comes to a "horror" moment.
All the religious posturing grows weary as the film goes on and even the craziness of the final act, can't really save the film from the weight of Mr. Reed's heresy. What saves the film though, is the terrific performance of Mr. Grant, who really seems to be enjoying himself as the film's villain.