This article aims for an account of materiality that helps apprehend race as a material reality while attending to its semiotic, aesthetic, and cultural signification. Through a close reading of Alfonso Cuarón's film, Children of Men (UK, 2006), the author argues that allegory is a figure for recasting the problematic of racial alterity as a materialist concern. Relying on Walter Benjamin's formulations on allegory as a privileged mode of representation under conditions of modernity, the author argues that alterity straddles the boundary between the corporeal and the ideational. Cuarón's film deploys certain cinematic strategies to represent difference: from disjunctures between sound and image and a cinematic obsession with lingering on “incidental” details that lends them allegorical significance to an extended chase sequence. The place of race and biopolitics in this film cannot be understood without examining how allegory produces meaning, and what saves allegory from a nihilistic surplus of meaning in the film is the figure of alterity, which in this film has become an allegorical emblem. The cinematic logic of this film, which stages racial and biopolitical issues as ones about visibility, suggests that alterity itself is what grounds the circulation of all the other signs. Allegory's claims are transhistorical, and when alterity is caught in its system of signs, it marks the transience of our own historical embeddedness, a double recognition that categories of difference regulating human organization and politics are as temporary and as transient as all historical artifacts. Alterity-as-biopolitics is also, however, a kind of traumatic sign that persists across history, and its meaning is often concealed. The article concludes with speculation about cinema's unique means of producing the truth about race.