 This is Crowd Science from the BBC World Service. I'm Caroline Steele. And I'm Marnie Chesterton. And we're stood outside what looks sort of like a house, but something's not quite right. So the windows aren't proper windows, they're ventilation slats. And then another big clue is all the security cameras on every single corner of the building. We're staying on the road because it's public property. LAUGHTER