This paper examines representations of historical guilt, agency, and transformation in Doris Lessing's novel The Grass is Singing. In particular, this paper argues that the warped interracial relationship between the novel's white female protagonist, Mary Turner, and her black servant Moses, becomes the vehicle for a cathartic and redemptive alleviation of white postcolonial guilt. The allegorical violence that infuses this narrative of atonement is historicized within the context of the Black Peril in South Africa and the heightened surveillance of feelings under apartheid. Mary's experience of guilt is analyzed according to Judith Butler's argument that subject formation relies paradoxically upon the twin experiences of both abjection and agency. Even as Mary's sense of historical guilt becomes a debilitating form of abjection, it encodes and bolsters powerful forms of agency. Mary's dementia is read as a symbol of J. M. Coetzee's more recent characterization of apartheid as an event of "collective insanity," and forms the basis for a broader critique of the limits and exclusions of white postcolonial guilt.