Abstract This essay uses affect theory to argue that Greta Thunberg's gestures, rather than the representational content of her speeches, innervates intense responses of admiration and contempt. In this essay, we depict these gestures, which includes Thunberg's school strike, speeches, and her refusal to fly, as shaming gestures. We then illustrate how Thunberg negotiates the rhetorical limits established by the affective dynamics of shame. Specifically, shaming demands rhetoric that is at once preeminently social but also individualizing or particularizing, since shame entails criticizing an individual for violation of a social norm or expectation. Shaming explains both the widespread identification and contagion Thunberg produces, as well as the heated contempt of detractors—both of which are common responses to shame. We conclude by discussing the limits and potentiality of shame, as well as gestures more generally, contending gestures become essential for social movements in a digital media ecology.