Paul Cornell, commenting on Fortean themes within the series, mentions that "Doctor Who" is a populist series exploring the public perception of the fantastic and that the Yeti stories are an early example of "Doctor Who" exploring such concepts, which were later explored in several serials produced by Barry Letts in the early 1970s. Media historian James Chapman agrees that "The Abominable Snowmen" is the first "Doctor Who" serial to explore cryptozoology or mythology with an alien grounding, also citing it as having drawn from the gothic horror atmosphere and plot of Hammer’s 1957 film "The Abominable Snowman". He reflects that their second outing, in "The Web of Fear", turned what was merely another monster when in the Himalayas into a nightmare by placing them in the identifiable setting of the London Underground. Chapman concludes that "The Web of Fear" also, by centring the Yeti threat in the London Underground, is part of a horror tradition where a 'chaos world' is located under the surface the ordinary.