Old-fashioned photographs were taken using glass plates treated with silver. (Some speculate that the use of silver is the reason vampires supposedly don’t appear in photographs.) Luke is in the middle of a crowd of Janissaries.
The streets of London.
Blood is the coin of life, the silver plate of memory and the soul. To drain someone’s blood is to absorb their soul into yourself.
It doesn’t matter if none of your own remains…when you have all these extra lives locked within you.
Kinda sucks for them, though.
Luke (thinking): To paraphrase my brother…what the bleep?!