that "some fungi do resemble soap suds, but the reverse isn't true: soap suds do not convince as a fungal menace" and, as such, "credibility washes away in the foam." Bryan Senn, the American film critic, says in a similar vein that "it's difficult to make a bunch of advancing soapsuds look menacing" and that "the creatures themselves are never shown too clearly, which is just as well since they inspire more menace in spongy silhouette than in full bubbly view (upon which they look just like what they are – actors with bits of dirty cotton stuck to their faces)." British film critic Phil Hardy writes that "the monsters are unintentionally hilarious – they are simply actors entirely covered in soap suds." And Warren says he "wonders hopelessly why the filmmakers didn't consider how audiences might react when they saw huge quantities of suds pouring down cave walls. It's not likely they didn't care ... it's more likely they sadly misjudged the look of their menace, and the intelligence of most horror and science fiction audiences." Two of the actors in The Unknown Terror have also commented on the special effects. Powers said in an interview that the fungus-covered monster-men's makeup "was just cotton, put on with a liquid adhesive or spirit gum." And while Howard called the monsters "just nonsense" in an interview, he also said that "in viewing the movie, I thought that it looked like soap bubbles coming down the cave walls. I didn't see how this would frighten anybody, but it sure frightened the hell out of my kids – they were scared to death!" Other critics have dug more deeply into the film, peering through the suds to find more complex meanings. American academic film historian Rob Craig notes a religious theme within The Unknown Terror. He writes that the songs performed by Sir Lancelot "are well used as purveyors of taboo folk wisdom, with one line, 'He's got to suffer to be born again,' vividly foreshadowing the ensuing religious emphasis on the film." As an example, Craig writes that when he's asked about the Cave of the Dead's precise location, "Ramsey chuckles, 'I can show you how to find that – it's their purgatory ...' as he points his spoon towards the flames under his boiling pot. A more literal reference to the fiery flames of the Christian Hell cannot be imagined and