Idea for Horror Film
Our protagonist is Paul, a young man who has recently moved to a new city where he doesn't know anybody. He’s feeling quit lonely and sad, but he likes to go to the city, sit in coffee shops writing and listening to music. Eventually Paul meets some nice people and they ask if he wants to go see some music. He goes along with them and it turns out they're part of a Pentecostal Christian church. This is not what he had in mind, but he humors them because they seem nice and he doesn’t want to be rude.
As the Pentecostal event ramps up Paul starts to get into it. The music is lively, the people seem happy, the preacher is saying stuff about love and community that makes sense to Paul. When the preacher asks if there’s anyone present who has not given their life to Jesus Paul puts his hand up (along with numerous other people scattered through the crowd). A little later in the service the Preacher does an altar call, inviting people to come up the front and give themselves to the Lord. Paul is feeling a bit too shy, so he doesn’t go up immediately and things start to get weird. There's laying on of hands, people are shaking and falling, speaking in tongues - the usual Pentecostal stuff.
Paul is starting to feel a bit freaked out now. He decides to try and lay low. He can't really sit down without drawing attention to himself, so he's sort of shrinking back. The service keeps going, music is ramping up, the people are dancing, etc. The preacher repeats the altar call several more times. Eventually he says, "I can still feel that someone in this house hasn't given themselves over to the Lord". His eyes search the crowd until finally he spots Paul. The Preacher points directly at Paul and invites him to come up the front. Things go quiet as the crowd waits for him to answer the call. Paul nervously starts to make his way out of his seat into the aisle. In the aisle he takes a step or two toward the front before turning and sprinting out of the building.
From that point in the movie, beginning with his rapid exit of the building, Paul is pursued by Christians. They seem manic and totally unconcerned for their own safety, but otherwise still human. They claim to want to bring him to the Lord, though whether as a convert or a ritual sacrifice isn’t clear. At no point in the movie do any of the Christians try to hurt him or do anything worse than restrain him. We don't see them consciously choose to hurt anyone else either (though they may accidentally endanger other people, for example by disrupting traffic). Paul, on the other hand, is not afraid to resort to violence in order to escape the Christians. They are scaring the shit out of him. At times they resemble a smiling zombie horde.
There could be a scene where Paul tries to get help from the police. They sound skeptical at first, but ultimately he persuades them to drive him to safety. Once they’ve put him in their car they take him back to the Christians instead. Paul manages to escape the police car, but ultimately the Christians catch him and drag him back to the building where the service is being held.
The last shot of the movie is Paul being carried inside the hall. Swallowed up by the light pouring from the building. His cries of protest drowned out by Christian music.