[Macfarlane spent several days with urban explorers in the Paris catacombs]

What can I tell you about my time in the invisible city?  That it is the longest I have ever gone without seeing sunlight.  That one night, or perhaps it is one day, we listen to ‘Dig for Fire’ by the Pixies, laying a phone against the wall of a tunnel so the limestone booms the track back to us and lifts our spirits and makes me smile.  That the evening we emerge, the Draconid meteor showers come, showing as silver scratches in the sky.