It has become relatively common practice within health professional education to invite people who have used mental health and social care services (or service user educators) to share their stories with health professional learners and students. This paper reports on findings from a postcritical ethnographic study of the practice of service user involvement (SUI), in which we reflexively inquired into conceptualizations of service user educators' knowledge contributions to health professional education in the accounts of both service user- and health professional educators. This research was conducted in response to recent calls for greater scrutiny surrounding the risks, challenges, and complexities inherent in involving service users in health professional education spaces. 'Story/telling' was identified as a pronounced overarching construct in our analysis, which focuses on participants' reports of both the obvious and more subtle tensions and complexities they experience in relation to storytelling as a predominant tool or approach to SUI. Our findings are presented as three distinct, yet overlapping, themes related to these complexities or tensions: (a) performative expectations; (b) the invisible work of storytelling; and (c) broadening conceptualizations of service user educators' knowledge. Our findings and discussion contribute to a growing body of literature which problematizes the uncritical solicitation of service user educators' stories in health professional education and highlights the need for greater consideration of the emotional and epistemic labour expected of those who are invited to share their stories. This paper concludes with generative recommendations and reflexive prompts for health professional educators seeking to engage service user educators in health professional education through the practice of storytelling.