Then I mentioned it to my partner and she observed the word iris also refers to part of the eye, so then I had another idea.
It got me thinking about those dreams when you're not sure whether you're awake or not and the sense of paranoia that can kick in. The idea of using artificial light made sense and I really wanted to add the EMF recording I'd made to the drums I'd recorded last month, so it came together quickly.
I experimented with a couple of basslines but ended up using a more rock sounding driving rhythm, although I had to clear some space among the lower frequencies. I also gated the EMF hum to pulse with the drums in places for a more 303-sorta sound and added distortion.