When extreme contexts reveal voids in national preparedness systems, the actors in emergent intermediaries face a dilemma in resolving a lack of supply—they can follow existing rules and fail, or they can break rules to enable supply but risk punishment after the crisis. Multiple-case analyses of how the COVID-19 outbreak affected the supply of safety-critical goods revealed how intermediaries emerged rapidly and contravened national legislation and customs because prosocial frustration compensated for fear. Those public and private actors involved in emergent intermediaries reflected on the right thing to do and envisioned a flexible national preparedness system. Although literature points to intermediaries for new coordination of supply during crises, their emergence and social organization into rapid institutional renewal are overlooked. Based on our findings, we develop a model that shows how new intermediaries emerge when actors break, make, and prosocially integrate rules by drawing on frustration and reflection to envision system renewal, institutionalize their experience, and avoid impending punishment. While theories overlook the dilemma of voids in national preparedness systems, this study highlights how emergent intermediaries’ actors renew institutions rapidly. These insights advance extreme context research on the phenomenon by integrating institutional and prosocial literature and offer policy implications.