BackgroundEnsuring that students transition smoothly into the identity of a doctor is a perpetual challenge for medical curricula. Developing professional identity, according to cultural‐historical activity theory, requires negotiation of dialectic tensions between individual agency and the structuring influence of institutions. We posed the research question: How do medical interns, other clinicians and institutions dialogically construct their interacting identities?MethodsOur qualitative methodology was rooted in dialogism, Bakhtin's cultural‐historical theory that accounts for how language mediates learning and identity. Reasoning that the COVID pandemic would accentuate and expose pre‐existing tensions, we monitored feeds into the Twitter microblogging platform during medical students' accelerated entry to practice; identified relevant posts from graduating students, other clinicians and institutional representatives; and kept an audit trail of chains of dialogue. Sullivan's dialogic methodology and Gee's heuristics guided a reflexive, linguistic analysis.ResultsThere was a gradient of power and affect. Institutional representatives used metaphors of heroism to celebrate ‘their graduates’, implicitly according a heroic identity to themselves as well. Interns, meanwhile, identified themselves as incapable, vulnerable and fearful because the institutions from which they had graduated had not taught them to practise. Senior doctors' posts were ambivalent: Some identified with institutions, maintaining hierarchical distance between themselves and interns; others, along with residents, acknowledged interns' distress, expressing empathy, support and encouragement, which constructed an identity of collegial solidarity.ConclusionsThe dialogue exposed hierarchical distance between institutions and the graduates they educated, which constructed mutually contradictory identities. Powerful institutions strengthened their identities by projecting positive affects onto interns who, by contrast, had fragile identities and sometimes strongly negative affects. We speculate that this polarisation may be contributing to the poor morale of doctors in training and propose that, to maintain the vitality of medical education, institutions should seek to reconcile their projected identities with the lived identities of graduates.