Answer: Secret Industry by John Pym: The stairwells and lift lobbies of multistorey car parks are not usually areas where people pause to admire the architecture, so John Pym used this to his advantage. The model walkways and ladders replicate their full-scale counterparts and are a playful way of suggesting an alternative, unseen service industry at work within the building. Superficially mundane, some people may use the car park for years without being aware of their presence, while others will notice straightaway. The artist sees it as a reward for those who look more closely at their surroundings.