Ling keeps asking the right questions, which in this show is the fastest way to end up on someone's list. A thread left dangling since E24 gets tied off at last, neatly enough to make a librarian smile. Where E27 hesitated, this one commits. The line of the week goes to "Why are you able to use alchemy here?", which deserves to be embroidered on a cushion. A comfortable, confident episode.