Dion Boucicault, the Irish genius of London theatre in the age of Dickens, wrote the brilliantly funny London Assurance in 1841 and thereby created - in Sir Harcourt and Lady Spanker - two of the great comic roles of the English stage, played at the NT by Simon Russell Beale and Fiona Shaw. This stage revival has been brilliantly adapted by the prolific and award-winning playwright Richard Bean.