They find that the city edge was rather close to them, and rather higher than it was elsewhere. There's a gigantic waterfall that goes over, fed by rivers that travel through the city. And at the edge is what appears to be a large glider.
The man in red starts chattering inanely as the glider is pushed forwards by several people in blank masks, masks without even eyeholes. And, with a surge of zero gravity, they're off... And plummeting.