- Author's Saving Throw: The Doctor takes Bill's concerns about being a black woman in an era where slavery was legally enforced very seriously, after "The Shakespeare Code" got some criticism for his blithely brushing off Martha's similar thoughts.
- Complete Monster: Lord Sutcliffe is a racist businessman from Regency England who happens to capture an alien sea creature. Trapping it into the bottom of River Thames, Sutcliffe found a particularly vile way of using the creature for personal gain. During the Frost Fairs, he would lure innocent people onto the ice where he would feed them to the creature. The creature would then defecate the human remains, which Sutcliffe would then have molded into bricks to burn in his mill, having discovered they burned vastly superior, as well as being cheaper, than coal. Sutcliffe has done this for many years, racking up a body count of possibly hundreds, children included. When the last Frost Fair occurs in 1814, Sutcliffe decides to plant explosives onto the ice's surface to detonate, destroying the ice and causing dozens of people to be devoured by the creature, and later straps The Doctor and Bill Potts onto them. Upon witnessing them escape and warning people to get off the ice, Sutcliffe goes forward with his plan and detonates the explosives attempting to kill them and anyone else still on the ice. Self-admitting to be without "an ounce of compassion" and solely motivated by greed, Sutcliffe is a perfect example that sometimes humans can be just evil as any extraterrestrial threat.
- Genius Bonus: Those aware of the etiquette of the time period (and/or more formal etiquette in the UK that the working class Bill would most likely not be exposed to) would know that sitting down in someone else's house without being offered a seat would be considered impolite and presumptuous; combined with the fact that Bill is a working class black woman in a male aristocrat's house in Regency England, such viewers would know without doubt that Sutcliffe would NOT be pleased when he arrives to find Bill seated.
- Moment of Awesome: The Doctor, of all people, very satisfyingly responding to Sutcliffe's vile dismissive racism towards Bill by flooring him with one hell of a punch.
- Special Effect Failure: The ice cracking under Lord Sutcliffe and his fall into the river were less than impressive.
- Strawman Has a Point: Sutcliffe defends his business by pointing out that more workers die in coal mines to produce a form of fuel that is vastly inferior to the alien seamonster poop he's harvesting. While the story's implication is that he's crossed the Moral Event Horizon by actively killing people, his point that with his business fewer people die, to make a better product, is actually a rather good one, and while he's openly callous, and a racist to boot (though not unusually so for his day), his attitude as regards the expendability of human life is Not So Different to that of some mine owners.
YMMV / Doctor Who S36 E3 "Thin Ice"