That Is All You Need To Know (which ran for 80 minutes or so; no interval) told the story of the Bletchley Park codebreakers and the parallel story of how enthusiasts struggled to preserve and restore the place in recent times. I thought it was highly effective, making good use of projections and recorded extracts to establish time and place, and a rather more numerous than normal audience in the Greenwich Theatre agreed with me.
The main male characters (Hugh Alexander, Alan Turing, Gordon Welchman) were effectively characterised, although doubling of the female ones made them a bit less clear. Many weighty themes were touched on lightly and skilfully–the fate of Alan Turing, for instance, or Gordon Welchman as being a kind of reflection of Oppenheimer–and I think the story of the preservation attempts showed that we were still confined within a frame of eternal England, rather than reducing it all to complete bathos, which it might easily have done.
I liked the fact that the contribution of the female wireless operators in intercepting and transcribing signals was recognised, and also that of the Poles in making initial breakthroughs and managing to pass on the necessary results and hardware. I was disappointed that there was no real attempt to illustrate the regularities in the Enigma-induced mapping that allowed it to be broken–explain would have been too much to ask, but a couple of visuals might have done the trick–the thing at the beginning about Turing pedalling backwards once every twenty revolutions might have been an allusion, but that was about it.
Well worth seeing!