Dame Diana Rigg. I tell you, that girl’s career is really taking off.

After thoroughly enjoying Rigg tearing things up as Grandmother Tyrell in Game Of Thrones these past few weeks, here she brings the sass with much more creep to the role of a Victorian ne’er-do-good with plans for global domination.

“The Crimson Horror” is in many ways the most assured episode of this current season, even if it didn’t necessarily thrill me in the ways I’d like. It brings back the Silurian Madame Vastra, her girlfriend / sidekick Jenny Flint, and the potato-headed Sontaran Strax. First introduced in “A Good Man Goes To War” and last seen in “The Snowmen”, the trio have proven to be a reliable extended family for the Doctor and a critical and fan success.

What made the episode unusual and interesting from the outset was the structure of leaving the Doctor and Clara out of the adventure for the first third. While it’s probably good for Smith and Coleman to get some down time (or time to spend on other episodes), it also allowed us to approach the mystery from a purely Victorian standpoint.

A young man is investigating the death of his brother at Sweetville, a mysterious factory up North. He brings the case to Madame Vastra, and the three travel to investigate a sort of temperance movement helmed by intimidating Mrs. Gillyflower (Rigg in full scenery-chewing mode). Bodies have been found entirely coloured red, and a local mortician has dubbed it the Crimson Horror. More than that, Gillyflower is selecting pure specimens to join her in a new community adventure named Sweetville. When Vastra discovers an image of the Doctor imprinted on the eye of the latest victim, they realize that their favourite time-travelling dandy is involved.

This section of the story unfolds nicely, and while the banter of the Paternoster Gang isn’t as strong as they’ve been written before, there’s still good mileage in the dynamic. Strax is bull-headed and violent, Vastra is calculating and intelligent, while Jenny is the human face (and talented martial artist) who can infiltrate enemy groups.

Eventually, Jenny does find the Doctor — crimson-ed himself, but still alive — and they set about rescuing Clara, foiling Mrs. Gillyflower, and making peace with Ada, Gillyflower’s blind, sympathetic daughter.

Once the Doctor is released from his crimson shell, he explains in a quick back-story just how he and Clara came to be trapped in Sweetville. A sepia-toned, beautifully edited rapid-fire series of scenes shows their arrival up North (the intention was to visit London), meeting Gillyflower, and being captured. The visuals throughout this section were a new departure, and beautifully rendered, but these flashbacks never really added anything to the narrative — it was all information that we could have assumed.

The crew eventually discover Gillyflower’s overarching plan: she’s been keeping an ancient leech quite literally close to her chest, and it’s provided the preservative that she’s used to freeze the “chosen few” who will occupy Sweetville’s new world. As for everyone else, well they will get a stronger dose, showered from a rocket high in the sky, poisoning the air and killing the others.

There’s a nice theme running through Gillyflower’s action, as she’s basically a slightly more jumped up version of temperance leaders who were terrified about the sin and corruption enveloping an industrialized Britain. It’s also given a human face in the form of Ada, Gillyflower’s daughter. Blinded in a supposed attack by her father, Ada is played by Rachel Sterling, Diana Rigg’s real-life daughter. The pairing works well, with Ada being the one piece of imperfection in Gillyflower’s life, albeit one she’s willing to cut loose by story’s end.

As I said, the constituent elements of this piece are fantastic: the Victorian setting and characters that worked so well at Christmas, a power-house mother-daughter acting pair, an unusual dramatic structure, and anchored by a very Whovian attempt to destroy the world.

It should also go without saying at this point that the thing was gorgeously realized. It’s fair to say that there is no show on television that is doing with visuals, set design, costume and direction what Who is doing right now — a feat tripled in difficulty by the fact that every week is a stylistic tabula rasa. The bell jars containing the trapped Sweetville residents, the speakers pumping out the illusion of a working factory, even lighter touches like the scarring around Ada’s eyes.

The story itself, though, never seemed to rise above the quality of these elements, never quite becoming greater than the sum of its parts. Once the Doctor was freed from his bind, it was just a case of watching as he, Clara and the gang solved each problem thrown at them with relative ease. The reveal that Gillyflower had built a rocket ship to poison the air was impressive, but never quite felt like it changed the texture of what was happening. It all barrelled along as expected.

The development that Ada had been blinded not by her father, but by Gillyflower herself in an attempt to experiment with the leech’s excretions, was a strong one. However, it would have been better if Gillyflower and Ada had had a good relationship; then it would have been a true betrayal and a true turn-around in their dynamic. Gatiss’ script and the Doctor make some good points to Ada about the morals of the time (and our own), about the Catholic guilt concept that drives Ada to believe her blindness is a punishment for some darkness in herself – but the relationships never quite carried this concept through.

Still, it was fun. Watching Jenny kick ass, Vastra terrify people whenever she whipped off her veil (which happened very frequently), and Strax’s chance to actually fire a laser gun. All strong. Rigg hammed it up, and the Doctor and Clara had some classic comic moments — especially when they brought their Northern accents to proceedings.

And how does this fit into the grander scheme of things? One of the episode’s bigger weakness was that it didn’t really justify why the Doctor had travelled back to that time, and originally attempting to go to London. He claims to Clara it’s because she might enjoy it, but it’s likely he was searching for info on her. Why, then, does he not bother explaining things to the Paternoster Gang, or quizzing the knowledgeable Vastra on what might be happening? It’s a big gap.

When Clara returns home from her trip, though, things take a step forward. The children she minds have discovered — through their, you know, children ways — pictures of Clara in various times, from the submarine in “Cold War” to the haunted mansion in “Hide”. There’s also a picture of Clara in Victorian London, which is odd as she rightly points she’s never been there.

This forces a confession from Clara on her recent adventures, and it looks like next week the Doctor will have two kids to contend with as well as the return of the Cybermen.

Another nice piece of the puzzle, then, for an episode that serves as a great example of what Who is, but a lesser example of what it can be.

Free Radicals

– I think it’s probably Gatiss’ writing (as Moffatt’s always written for the Paternoster Gang), but it felt like Vastra and co. don’t have much mileage left in just the Victorian setting. Here’s hoping that when they return — which they probably will — it will be a different back-drop.

– There were several moments where we were supposed to believe that Matt Smith and Jenna-Louse Coleman are incapable of catching or over-powering 70-something Diana Rigg. Awkward.

– I love the moment when the gang were looking out on the factory, and then we pan up the rocket. Then, after we’ve gotten that money shot, they point out the rocket — even though they haven’t moved they’re suddenly now capable of seeing it, once we have.

– I talked a lot about Clara last week, and again this week the character felt unsure, high on quippery but not much else.

– I’ve started to become one of those people who gets annoyed with the Who score. Turn it down, people!

– I hate children. But Neil Gaiman’s writing next week’s episode so hopefully it will be okay.