It finally happened. Like scratching that lottery ticket and winning $100, we finally got a Doctor Who episode this season. We’ve had decent ones and painful ones, but with "Kerblam", we finally have a real one.
First, we have links to the past that we haven’t really seen up to now. The fez was obvious but welcomed and the Agatha Christie comment was icing on the cake. Next, we have the Doctor blundering into a situation without any plan. She actually gets in the way by overthinking things when the system initially puts her in custodial. It was much more of a fluid situation which she had to adapt her plans to on the fly as opposed to "Rosa" and "Demons of Punjab", where she was basically protecting a forgone conclusion. Also, The companions were real active in parts of the plot instead of being sent away on some unrelated side quest. And finally, the thing that put it over the top for me was the twist. Making a common item scary or dangerous is a long tradition (Autons and Angels to name a few), and lethal bubble wrap just adds to this. I don’t know if it was an intentionally homage to the green bubble wrap monsters in arc in space, but I like to think it was.
In other words, this episode had a nice mix of mystery, fun, history and some relevance to today, as a good episode should. Without hitting us over the head with it. I’ll give it 4.5 out of 5 Tardises.