The strike of midnight is not heard very loudly at Turnmills. At weekends, the London nightclub is open until 7am; the evening has barely started as I arrive on a Saturday night just before the witching hour. Inside, groups of wide-eyed twentysomethings wander the labyrinth of corridors and stairways that link the dungeon-like venue, while stressed-out security guards in high-visibility vests prod and bark at anyone who might be tempted to dawdle.

On the club’s main dance floor, a laser light show illuminates the scene: hundreds of perspiring clubbers lift their hands to the ceiling as the DJs play a juddering soundtrack of pounding house music. Stopping for a beer, I am struck by how few people are queuing at the bar.