New Yorkers are accustomed to strange sights on their streets. But this week, even hardened commuters did a double-take. Police are investigating grainy footage of men emerging from the city's sewer system.
Not as part of maintenance work. Not as part of a film shoot. They appeared, blinking in the daylight, and then vanished into the crowds.
The videos, shared widely on social media, have sparked a security alert and a flurry of speculation. Are these urban explorers? Tunnel dwellers?
Or something more organised? The authorities are tight-lipped, but the public imagination has run wild. For those of us who walk past grates and manholes every day, it is a reminder that the city has a life below the pavement.
A hidden layer. And whatever is down there, it is now coming up for air. The human cost?
A collective unease. The cultural shift? A new fear of the dark.
Or at least of the dark below our feet.
