Mark Gatiss' second Doctor Who script for this series takes us back to Victorian London with the Paternoster Gang. Warning - the following review contains spoilers, don't read if you haven't read the episode!

Mark Gatiss proved three weeks ago that he can write amazing Doctor Who stories. Cold War was a near perfect reintroduction for the Ice Warriors, and was Gatiss' best script since 2005's The Unquiet Dead. So how does his latest story, The Crimson Horror compare? Well, while it isn't on par with Cold War, it comes close!

The Crimson Horror sees the Paternoster Gang, consisting of Madame Vastra the Silurian (Neve McIntosh), Strax the Sontaran (Dan Starkey) and Jenny Flint (Catrin Stewart) investigate red bodies found floating in the Thames.The trail leads them to Sweetville, a village in Yorkshire where only 'perfect' people are allowed. There, they encounter the Doctor (Matt Smith) and Clara (Jenna-Louise Coleman), and together, they have to stop Miss Gillyflower (Dame Diana Rigg) and the mysterious Mr Sweet from killing every 'non perfect' human on the planet.

Recently, Doctor Who has, once again, become more Earth-bound, specifically, in Victorian London. This is no doubt done so that the Paternoster Gang, and extremely popular group of characters, can feature more often. However, I find this rather boring and repetitive, as I'm not really fond of the Gang, and generally find them to be boring and uninteresting. However, with The Crimson Horror, Mark Gatiss has managed to bring life the two members of the Gang who so far have been disturbingly underdeveloped. Jenny is put in the spotlight here, and demonstrates that she's quite good at infiltration and subterfuge, as well as showcasing a knack in martial arts in a sequence that reminded me strongly of a scene with Black Widow in Iron Man 2. Strax, as always, is sort-of funny, but his appearance here is made tonnes better by the fact that the Doctor isn't patronising him every two seconds. Unfortunately, the Doctor's role of teasing Strax is filled, to a degree, by Madame Vastra, who, other than reprimanding Strax for having his first good action scene since A Good Man Goes to War, doesn't really do anything; she's a background character, much like Jenny was in The Snowmen.

The Crimson Horror played the wild card by only introducing the Doctor and Clara halfway through the episode. The reveal of the Doctor was well done, with clues dotted everywhere, from the image of the Doctor imprinted on the dead man's retina, to Ada (Rachael Stirling) keeping a 'monster' as her pet. Once the Doctor has been cured from his red condition, we are treated to a wonderful sepia-style flashback detailing the Doctor and Clara's own, failed attempt at finding out what's happening at Sweetville. For the fans of the Classic Series, there's a reference to the Fifth Doctor's companion, Tegan (the 'gobby Australian' the Doctor describes). In Doctor Who's 50th Anniversary year, these small references are a very nice link to the past of the show.

All the cast, as usual, are on top form, but the standouts of the episode were Diana Rigg and her daughter, Rachael Stirling. It's quite obvious that the episode was constructed around their relationship (indeed, their characters are even mother and daughter!), and Rigg and Stirling relish the opportunity to act alongside eachother. Rigg is pitch perfect with her portrayl of an insane Miss Gillyflower, while Stirling underplays the pain and suffering of Ada beautifully. It's a shame, though, that the fact that the episode is set around the two, does occasionally detract from the viewing experience; it sometimes feels like the plot, cast and action is shunted to the side in an effort to further explore the relationship between Ada and her mother.

The identity of Mr Sweet was unexpected, I was actually expecting to see the Great Intelligence turn up again after his defeat in The Snowmen (but I suppose he's off in Tibet building some Yeti), so the reveal that Mr Sweet is a leech was a nice surprise. However, the fact that the leech is recognisable to Vastra, and was the cause of a great plague to the Silurians, was extremely contrived, and I suspect the link was only made in order to have the protagonists deduct what the red goo was (a poison secreted by the leech).

The humour in the episode was quite good, in particular, I laughed at 'Thomas Thomas', a reference to the GPS service TomTom, and the 'screwdriver and chair' exchange between the Doctor and Clara. Finally, a writer has realised the the sonic screwdriver is overused!

The Crimson Horror is by no means perfect, however. How did everyone survive the rocket's thrust when they're all standing in the launch silo? Turning your back does not mean you will survive without a scratch or burn! How did Strax get down from the top of the silo to the staircase in a matter of two seconds. And what exactly was Miss Gillyflower's motivation for wanting to wipe out most of humanity? It's never really explained clearly, but it is hinted that she found society disgusting and wanted to start again (similar to Operation Golden Age in Invasion of the Dinosaurs).

At the end of the episode, we have the first instance where a companion's associates have successfully deduced the companion's time travelling experiences with the Doctor, without questioning the Doctor directly or having their own TARDIS journey. It was quite amusing to see Clara bewildered by Angie and Artie, as the children show her photos of her from the 1970s and 1980s. In the end, they blackmail her into letting them travel in the TARDIS. It will be interesting to see how this plays out!

Overall, The Crimson Horror is a fun romp that doesn't add anything to the overall arc of the series. With strong characters, great investigation and successful humour, the episode is thoroughly enjoyable. Some unrealistic physics, the patronisation of Strax, and a hazy motive don't greatly reduce the viewing experience.

8/10

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