Some time I think in 2012 I saw a horror movie on my cable systems on demand section.  It was a British film about a group of young people in a flat living a normal life.  Then out of know where one of the friends a guy goes nuts talking about invisible monsters are trying to get inside and murder them all.  I don’t quite remember in between, but I do know that one of the friends, another guy got tired of the crazy guy.  A big fight happened when not crazy guy tried to leave the flat and crazy guy attacked him.  They ended up killing each other if i’m not mistaken.  There was a girl also in the group.  Now with both guys dead, she felt the other guy was nuts. So she goes out the door.  The film fades to black.  Apparently on their flat was something like a fourplex with a lobby.  So there was their door to the flat and there was a lobby with a door to the outside.  So when you expect the credits to roll. The screen fades in.  And you have a slow pan on the girl torn to shreds by something that wasn’t human.  And then we fade to black again.  Roll credits.  I cannot remember the name of this movie at all.  I only saw it that one time because It disturbed me.  Can anyone remember it?