During the COVID-19 pandemic, scientific information served as the basis for political decisions and individual actions. We argue that in such large-scale emergencies, audiences seek more than information: they seek trusted individuals, like scientists and public-health experts, who have expertise in relevant areas. Celebrity scientists are mediated personae who not only convey information, but also offer audiences social cues. Specifically, audiences can develop parasocial relationships—a sense of knowing a mediated figure—with well-known scientists. Additionally, celebrity scientists provide audiences with reassurance that experts are dealing with the problem, thus reducing anxiety. This chapter proposes that trust in science is, to some extent, fuelled by public-facing scientists. We review relevant research on trust in celebrity scientists as well as conceptual approaches that may explain motivations for seeking out celebrity scientists, ranging from information needs to emotional gratifications to parasocial relationships. We also synthesise empirical studies of celebrity scientist effects in these areas. Finally, we conclude by discussing the implications for health and science communication.