I saw it on a first aid course of all places.
There's two women and a man. The man and woman(I think all are in their 20s) are talking to the other woman as though she's in trouble or they're trying to convince her of something. I think her name was Edna or Enid. It looks like they're in an empty cafe or similar. There's possibly some music posters on the wall. They're trying to persuade her of something and she said "Look what happened to Dalziel or some name like that. Then one arm shoots up in the air and she freezes then falls to the floor and seems to have some seizure but apparently she's actually being possessed.
It's driving me crazy trying to figure out what show or film it's from.
TIA