While being structurally subordinate, prisoners are neither powerless nor mute. Drawing on semi-ethnographic research in a Ukrainian medium-security prison for men, in this article, I advance the concept of ‘negative visibility’—that is, an administration’s fear of external attention and intervention, and make a case for the interplay of prisoner resistance with a managerial culture. Using Soviet penal and managerial legacies as an example, I argue that structure can be both constraining and enabling even within the milieu of the gross power imbalance of which prison is an archetype, thereby attesting to the coherence of agency and structure and the contingency of power. Furthermore, by highlighting that prisoners may undermine officer power for all sorts of reasons, including opportunistic and selfish ones, this study cautions against romanticizing the ‘defences of the weak’ and a priori politicization of prisoner resistance.