I suspect that more than half the audience that goes to see Dirty Dancing on stage has seen the 1987 movie, and that quite a few of them have seen the stage version more than once. There’s a strange feeling of being at a party where everyone knows everyone, and the party’s held nightly at the same house. It surely is not the misleading title that accounts for the wildly enthusiastic flow of fans - there’s nothing dirty about this squeaky-clean story, and there’s not that much dancing either. No, it must be that eternal celluloid magic, the girlish fantasy of entering a favourite movie and touching Patrick Swayze’s ghost.