Well, the concept behind this story really has been stuck in my head for a few years now. It was just waiting for a suitable storyline to accompany it. In quick flash of inspiration today, this has now made itself known to me. Set in London, all I need now is a bit of spare time to do a little work on it...
Given the setting of this folk horror tale, I think a timely sharing of an audio recording I made a few years back in the London Underground: