Greek tragedy: the chorus tells you what is about to happen; it happens; the chorus tells you what just happened. So how do you stage it nowadays? Carrie Cracknell, whose brilliant Doll’s House was one of the best things I saw last year, does it pretty much straight, playing it through with no interval in a fairly modern setting. The result is astonishing. Helen McRory as Medea dominates the stage, pulling the audience into her anger and desire for revenge. I was so grabbed by it that I had to look at my iPhone to check that 90 minutes really had gone by. The twitching dance of the chorus of Corinthian women seems slightly awkward at first but cleverly builds up with Goldfrapp’s excellent music to add even more intensity to the climactic moment when Medea murders her children. This is what the National Theatre at its best is all about. I hope that Nicholas Hytner’s replacement, Rufus Norris, can maintain it.