The Crimson Horror
The Crimson Horror was the eleventh episode of the seventh series of Doctor Who produced by BBC Wales. It featured the return of Madame Vastra, Jenny Flint and Strax, who were last seen in The Snowmen. It was the 100th episode of Doctor Who since its revival in 2005.
Madame Vastra and her partners, Jenny and Strax, investigate “the Crimson Horror” — a mysterious condition leaving victims with red skin and preserved like statues — after discovering that one victim has the image of the Eleventh Doctor visible in one of his eyes.
Investigations lead them to Sweetville, an idyllic community run by Mrs. Winifred Gillyflower and her never-seen “silent partner”, Mr Sweet, apparently as a home for the chosen few to help them survive “the coming apocalypse”. Jenny goes undercover as a convert and infiltrates Sweetville, where she discovers the Doctor, chained up in a cell, but only partially preserved; the process didn’t work because he was not human. Gillyflower tends to dispose of such “rejects”, but he has been saved by her blind daughter, Ada Gillyflower, who has become infatuated with him and describes him as “my monster”.
The Doctor is able to reverse the process on himself and he and Jenny go off in search of companion Clara Oswald, who has also been preserved. This confuses Jenny, as she saw Clara killed by the ice woman months earlier. The Doctor tells Jenny that he and Clara were actually aiming to visit London in 1893, but they instead arrived in Yorkshire. They immediately got involved in the investigation of Sweetville and the red bodies piling up in the sewers. The Doctor and Clara, posing as a married couple, joined the Sweetville community to investigate, but Mrs Gillyflower imprisoned and preserved them. The process worked on Clara, but not the Doctor; Ada locked him away, keeping him as her “special monster”.
The preservation process on Clara is successfully reversed, and Madame Vastra says the substance used to create the “Crimson Horror” effect is the poison of the red leech, a parasite the Silurians considered a major threat, 65 million years ago. The Doctor and Clara confront Mrs Gillyflower, who explains her plan and reveals that Mr Sweet is in fact a red leech who has attached himself to her chest. Their plan is to launch a rocket into the skies over England and spread the leech’s poison over the planet. Ada, listening in, learns of her mother’s plans and confronts her; meanwhile, Clara disables the rocket launch controls.
Holding a gun to her daughter’s head, Gillyflower retreats into the rocket silo to activate a secondary launch control; she launches the rocket, but learns moments later that Vastra and Jenny have removed the poison payload. She fires at the Doctor, but misses. Strax, who has climbed the chimney from the outside, returns fire, causing Winifred Gillyflower to plummet to her death at the bottom of the silo.
As the old woman lays dying, Mr. Sweet abandons his host. Ada shares final words with her mother before brutally killing the parasite with her cane.
Later, the Doctor returns Clara to her 21st century home, where she discovers that the two children she helps care for, Angie and Artie Maitland, have found images of her and the Doctor in different points of time — including a nuclear submarine in 1983 and a manor house in 1974. They have found an image Clara does not recognize; it was taken in Victorian London — but she’s only been to Victorian Yorkshire. The children threaten to inform their father that their nanny is a time traveler unless she takes them on a trip in her time machine.