Read the comic here.
Another new set today - it's a bit slapdash as I was distracted by other projects. Luckily I still had the "plain grey wall" left over from the Advent sets. It works just fine for this new room. I was playing with the lighting, too - the from-the-side shadows gives a slightly more dramatic feel to things, I think.
Finally, I don't normally like making my puns this explicit. I didn't think that "metadoor" would come across right without a little extra help, though.