YMMV / Doctor Who S33 E11 "The Crimson Horror"

• Accidental Innuendo: Many have pointed out that the episode's title sounds like a euphemism for menstruation.
• Aluminium Christmas Trees: There really were planned company towns for workers in both Europe and America where everyone lived next to their factory (Hershey being a notable American example). Such communities, in which workers were paid by a truck system (a.k.a. "cash" that can only be spent at the company store), were more of the "slow, mundane, awful" horror rather than alien leech venom horror.
• Complete Monster: Mrs. Winifred Gillyflower presents herself as a kind-hearted, altruistic old woman, but is really a psychotic madwoman who stands out through sheer scope. Opening Sweetville factory, publicly portrayed as a vision of the future, the entire place was really a trap so she could kidnap those she deemed "perfect". Through the manipulation of Red Leech venom, Mrs. Gillyflower brainwashed her followers and put her victims into suspended animation, any "rejects" simply tossed into the sewers. Mrs. Gillyflower planned to launch vast quantities of the poison into the atmosphere, wiping out all life on Earth, simply so she, and her chosen few, could create a new Eden in her image. She denies her own daughter, Ada , a place in her new world condemning her to death because of Ada's blindness—even though it was she who blinded Ada, when experimenting upon her with the venom to provide a cure for herself. Revealing herself to be nothing more than a cruel hypocrite, Mrs. Gillyflower was willing to murder all of humanity just so she could live out her fantasies.
• Hilarious in Hindsight: The Doctor's Yorkshire accent in this episode might leave much to be desired, but in two regenerations, they really nail that accent.
• Moral Event Horizon: When Mrs. Gillyflower is revealed to have experimented on her daughter with red leech venom, leaving her blind and disfigured, before blaming her late husband and manipulating her into helping her with her plan to wipe out humanity while secretly planning to let her die with the rest of humanity because of said blindness.
• Special Effects Failure: Although only noticeable if you're looking for it, just before Strax's "play with my grenades" line, you can see his face mask is starting to peel off.
• They Wasted a Perfectly Good Plot: The basic premise of this episode was that we'd get to see Jenny, Strax, and Vastra on an adventure, and the three are rather popular characters. The problems stem from the fact that it takes a rather short amount of time for the Doctor to get back into shape in the plot, and the three characters becoming secondary characters once more after the Doctor recovers, meaning we don't get to see the three's backstories explored in more detail.
• Ugly Cute: Despite the fact he's a parasite, Mr Sweet◊ was actually quite endearing to some viewers. Some were even sad when Ada killed him. It helps that, though a parasite, it just wanted a host to survive, never demonstrating any sentience. "Let's freeze-dry the people I deem "perfect" and wipe out everyone else with the worm-thing's venom, including my own daughter, since "blind and scarred" is imperfect, never mind that I'm the one who did it to her" was 100% Mrs. Gillyflower as far as we could see.
• The Woobie: We only got a glimpse of what Ada's life was like. We now know the truth is much worse thanks to her mother.

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