Except when computerised graphics show video film of a train crash in slow motion, there is nothing spectacular, theatrical or revelatory about The Permanent Way. But as with Justifying War, the recent dramatisation of the Hutton Inquiry into David Kelly's death, a stage performance clarifies, vivifies and illuminates. The production is based upon actors' interviews with unnamed people who are all linked to privatisation - from a High Powered Treasury Thinker and A Very Experienced Engineer to a Bereaved Mother. Hare has neatly woven these characters together, as if embroidering a great Victorian tapestry that illustrates How They Ruined Our Railways.