Improvised indie comedies are often dry and rarely achieve more than mildly amusing. You’ll occasionally get something that breaks the mold and is genuinely funny. While The Little Hours starts off shaky, it does eventually find itself and manages to be a pretty good movie.

Father Tommasso (John C. Reilly) runs a convent of irreverent nuns. Sister Marea (Molly Shannon) is kind of the head nun, but the “young blood” consists primarily of sisters Alessandra, Fernanda, and Ginerva (Alison Brie, Aubrey Plaza, and Kate Micucci). The younger sisters are often foul-mouthed, ill-tempered, openly hostile, and a real headache for their superiors. Their latest shenanigans have resulted in the groundskeeper quitting.

Massetto (Dave Franco) was a servant in the house of Lord Bruno (Nick Offerman), right up until the time that Bruno caught him sleeping with his wife (Lauren Weedman). Now Lord Bruno wants to kill him, and in the course of fleeing, Massetto happens to run into a very drunken Father Tommasso. Together, they hatch a plan that will grant Massetto asylum at the convent as long as he agrees to be the new groundskeeper and pretends to be a deaf-mute.

While the plot is loosely based on an Italian story from Giovanni Boccaccio called The Decameron, it was heavily improvised, and that’s pretty clear a lot of the time. Initially, the film seems to rely heavily on a couple of very thin tropes. It tries to find humor in the juxtaposition of modern language in a medieval setting, and in the juxtaposition of crude, vulgar language coming from the supposedly pure nuns. But fortunately, these dark days don’t last too long, and it manages to find some actual comedy. Everyone seems to be playing themselves, and none more so than Fred Armisen, who nevertheless manages to be funny in his small part as a bishop.

The Little Hours is pretty good, as far as vulgar medieval nunsploitation comedies go. It may rely too heavily on shock value, and it would benefit tremendously from an actual script, but a solid cast that meshes well manages to salvage something that easily could have been a disaster.