I once watched a travel documentary with Griff Rhys Jones in Paris, where he meets an underground group of people that sneak into official buildings at night an

I once watched a travel documentary with Griff Rhys Jones in Paris, where he meets an underground group of people that sneak into official buildings at night and repair things, they apparently have access to pretty much every building in Paris: https://www.youtube.com/watch?v=nLkl0r0C1ro https://www.youtube.com/watch?v=nLkl0r0C1ro (Section starts at 36m in) Maybe they're already repairing it?