Some kids throw a graduation party at a house. One of them does card tricks and talks about religion and falsifiability. He suggests they play an alternate Ouija game using labelled cards. They start asking questions mostly about sex. There are some unresolved romantic issues among the group. They fail to end the session with "good bye" and something breaks the glass they've been using.
They spend time in the jacuzzi playing "Never Have I Ever" which reveals some more about the characters. Afterward, finally, one hour into the movie, one of the character shows some strange signs. She displays some magic tricks of her own, starts talking in unison while someone else is speaking and can even say ahead of time what the other person is about to say. Things eventually turn deadly as the weird girl starts looking sick and recites biblical passages about the devil. Things turn strange as she seems to have some control over time as well. The innocent girl, who has some dark secrets of her own, will have to figure out a way to survive all this.
Nocturne managed to surprise me. It's smart, has a good story with some surprises, attractive actresses, some nudity, and a bit of gore. I have such low expectations of lower-budget horror movies these days but this movie is better than most. That said, it takes too long for things to get going, once the action begins it had my full attention, but the character are stuck acting nonsensically. I'm also not crazy about the dark sepia look of the movie. Nocturne represents a strong effort by a small production team.