IT’S highly improbable that Crunchem Hall would pass its Ofsted inspection. The school’s motto is “Children are maggots,” disciplinarian headmistress Miss Trunchbull picks up pupils by their pigtails and throws them into space and punishments meted out include being sent to chokey, a cupboard lined with sharp objects.

This sadistic vision of the adult world easily matches Roald Dahl's original text for Matilda. If anything, the crisp and biting lyrics of composer Tim Minchin and the script of Dennis Kelly send it into even darker territory.

Their gleeful anarchy make the Royal Shakespeare Company production an unlikely hit in an age of play-it-safe jukebox musicals. Since it opened in 2010, it’s won numerous awards and toured large swathes of the world. Part of its box-office success is down to its cross-generational appeal but its intelligence also means it reaches people who don't usually like musicals.