Readers will doubtless recall the Chichester Festival Theatre warning patrons that its production of The Sound of Music, one of the most famous and widely-seen musicals in the world, would contain references to Nazis. Which, for some, would apparently come as a surprise. More recently, the Royal Shakespeare Company felt it necessary to forewarn visitors that its production of Hans Christian Andersen’s dark fairy tale The Red Shoes features both loud music and “haze.” Because in a tale of mind-controlling shoes and amputated feet, the haze is the thing you really want to watch out for.