Luckily I missed that part. We left somewhere after the dinner scene with the bad omelette. The closeup stuff was making my wife dizzy anyway, and I just couldn't take anymore.
As for the gun issue, remember that this is Britain. No guns allowed. Even most of the police force don't carry, with the exception of one burb that was forced to start carrying for the first time in their history. Because of the sharp rise in gang gun use after the ban.
Hey, did anyone notice that a couple of times in the beginning of the movie (while the guy was exploring) the camera man slipped and everything was actually in focus for a second or too? Couldn't see a reason for it any of the times it happened, so it seems like a mistake. Better taste winning over instructions for a moment perhaps?
