
My review of the previous episode: Smile.
Thin Ice is just about everything I love about Doctor Who, from its compelling, evocative setting to its epic, spooky monster to its deft mixture of the serious and the silly. It's easily my favorite of this season, one of my favorite Capaldi episodes overall, and a welcome second installment from promising newbie Who writer, Sarah Dollard.
Bill and the Doctor arrive on the frozen Thames in 1814. When a street urchin steals the sonic screwdriver, the Doctor and Bill chase him out onto the ice, only to watch as the boy is sucked beneath the ice by mysterious green lights. Why? Well, it turns out a massive creature is sleeping beneath the Thames, devouring unwary Fair-goers and turning them into a super-powered fuel. A predatory aristocrat is promoting visitors to the Frost Fair to amp up production.