[Neil Jones]

It's especially odd because the whole concept assumes the viewer was watching from the beginning. If you happen to tune in five seconds later, or five minutes later, you're on your own!

On occasion you get a warning after a commercial break when you return to the programme.
Obviously this can't happen on the BBC so...

Of course it's like the classic case of Ghostwatch - if you came in after the introduction, you wouldn't a clue what to expect:
www.youtube.com 

Though the main problem here is people thought that was a) real, b) live and c) genuine. In reality it was all scripted and had been recorded weeks in advance. I think there was a phone number in it that if you rang it for some reason I can't recall now you were told the whole thing was a work of fiction.

No amount of warnings can help if you come in late to, well anything basically.