What is the world made of? In games and films the answer is often surprising. There is a wonderful moment in Inception in which Ariadne – Jesus, Nolan – takes a Parisian boulevard and folds it over on itself. It’s one of those instances of sheer cinematic glory: the horizon rises up and bends back, until buildings rest overhead and the sky is dark with tarmac and cobbles. Beyond the effects, what sells this moment? The reactions, certainly: DiCaprio as ever gets a lot into the business of doing very little. But there’s also a sound effect that for me elevates the whole thing. What should it sound like for a city to fold over on itself? In Inception it sounds both sparse and industrial: the core of the thing is the sound of an iron support pinging and creaking under growing strain. Paris is made of limestone, isn’t it? But in Inception, for this instance, it’s really made of iron: the framework bends and flexes but will ultimately hold. Paris, like Irn Bru, is made of girders.Inception is a movie with architectural preoccupations, so perhaps this flair for buried structure should be expected. Monument Valley, which I’ve been playing…