And Then There Were None – Theatre Royal, Norwich This is one of Agatha Christie’s best-known works and sums up all that’s great about her everlasting appeal. The plot is tricky, twisting and turning with red herrings aplenty, there’s a bunch of dubious characters, all thrown together in an isolated and menacing situation, and then murder upon murder! It is creepy throughout, with lots of shadowy darkness, and sees a group of strangers stranded on a tidal island just off the Devon coast. As is often the case with Christie, the audience quickly discovers that the guests are not quite as they se…