I'm lost in the corridors of the Dorchester Hotel, feeling a little like Hugh Grant at the end of Notting Hill - ruffled, desperate and in search of Julia Roberts. Two burly minder types are guarding an open door, so I peek inside. A press conference is in progress. I can't see Julia, but in her stead is a veritable feast of Hollywood leading men - George Clooney, Brad Pitt, Matt Damon and Andy Garcia are sitting in a line, firing quips towards a battery of salivating hacks. I'm politely nudged away from the door.