One of the key things to know about Wicked, the big-screen adaptation of the smash-hit Broadway musical, is that it’s not actually a big-screen adaptation of the smash-hit Broadway musical: it’s an adaptation of the first half. The title, on the screen if not on the posters, is Wicked Part One, and it ends with the caption “To Be Continued”, so viewers should be warned. We’ve had similar tricks played on us by the makers of Mission: Impossible – Dead Reckoning, and Harry Potter and the Deathly Hallows, but it’s still frustrating to realise that you’re only halfway through the plot after two-and-a-half hours, and that Part Two won’t be in cinemas for another year. It’s like being turfed out of a theatre at the interval.