Picture the scene. It’s a murder mystery play. Written by Agatha Christie. Already a recipe for success, just look at the mega power that is ‘The Mousetrap’. But wait, it’s a courtroom drama, and it’s being performed in London County Hall’s Council Chamber, giving the sense of a real court room. Ladies and gentlemen, I think that we are on to a winner here. This is ‘Witness For The Prosecution’.   Christie herself named ‘Witness for the Prosecution’ as her favourite play and