Design fiction, as a discursive practice, pushes for speculative scenarios that can be envisaged as a means of stimulating debates about societal questions. Indeed, Design fiction can foster a certain pluralism of visions that necessarily have to co-exist within a public policy-making process. Through ProtoPolicy, a design experiment, this article demonstrates how design fictions might help public institutions and communities of interest to consider and then debate the different implications of upcoming policies. With the issues related to ageing used as a starting point, ProtoPolicy proposes two design fictions especially co-designed to reveal the problems of social isolation and loneliness. By presenting these future scenarios to policymakers, civil servants, and citizens, ProtoPolicy aims at triggering discussions and reactions that will help to further adjust the trajectories of public policies.