Stepping off the tube at Holland Park, you can always hear it before you see it. The rhythmic soca beat thuds in the distance, faint echoes of singing and cheering cut through the usually rarefied quiet. A colourful trail of feathers and tinnies provides a makeshift route map, weaving through the pristine streets of Ladbroke Grove until you burst all at once into a cacophony of sound and smell, swept into a kaleidoscopic parade of gyrating hips and infectious laughter.