This chapter investigates the phenomenon of the uncanny in animated media. The uncanny valley effects, some have claimed, may reveal an innate ability to detect the boundaries between the human and the nonhuman in pictures. The chapter also investigates the hypothesis by describing the psychological mechanisms and the particularities of human biology that can predispose to the effects. It considers Sigmund Freud’s approach on the topic, as it reveals cultural aspects related to the phenomenon. The chapter describes the esthetic mechanisms that are more likely to induce disquieting effects in computer- generated (CG) animation. It suggests that uncanny feelings can analogize negative responses toward what is queer and different. CG animation produces facial expressions that elicit a continuum of emotional responses, ranging from awe to repulsion. The chapter analyses the origins of the expression “the uncanny valley” and explanations given about the causes of the sensation of strangeness elicited by synthespians.