Rupert Grint describes it as like watching a row of dominoes falling towards you, and when we emerge from a cellar bar in central London, climbing up to street-level Soho, it's clear he's caught it just right.
A few strides in the direction of his hotel and a face among a group of outdoor lunchers flinches in recognition, prompting other heads to turn and look. Quickly a chipper twentysomething is bounding across the road, dodging motorbikes, his cameraphone outstretched as if it's something Grint has mislaid. "Would you mind, Rupert, if we?" I'm sure this happens to other people with famous faces, but does it happen to quite such a degree?