Creepiness, McAndrew says, comes down to uncertainty. “You’re getting mixed messages. If something is clearly frightening, you scream, you run away. If something is disgusting, you know how to act,” he explains. “But if something is creepy… it might be dangerous but you’re not sure it is… there’s an ambivalence.” If someone is acting outside of accepted social norms – standing too close, or staring, say – we become suspicious of their intentions. But in the absence of real evidence of a threat, we wait and in the meantime, call them creepy. The upshot, McAndrew says, is that being in a state of “creeped out” makes you “hyper-vigilant”. “It really focuses your attention and helps you process any relevant information to help you decide whether there is something to be afraid of or not. I really think creepiness is where we respond in situations where we don’t know have enough information to respond, but we have enough to put us on our guard.”

Human survival over countless generations depended on the avoidance of threats; at the same time, humans thrived in groups. The creeped out response, McAndrew theorized, is shaped by the twin forces of being attuned to potential threats, and therefore out-of-the-ordinary behavior, and of being wary of rocking the social boat. “From an evolutionary perspective, people who responded with this creeped out response did better in the long run. People who didn’t might have ignored dangerous things, or they’re more likely to jump to the wrong conclusion too quickly and be socially ostracized,” he explains.

Dolls inhabit this area of uncertainty largely because they look human but we know they are not.