Background <p>Toxic nurse-manager leadership is a critical threat to patient safety, yet the mechanisms through which it suppresses adverse-event reporting remain under-theorized, particularly in high power-distance contexts where deference norms may constrain upward voice.</p> Aim <p>To generate practice-relevant, theory-informed explanations of how nurse-manager toxic leadership behaviours are perceived to shape adverse-event reporting dynamics and care quality within a high power-distance hospital setting.</p> Methods <p>An interpretive descriptive study was conducted in a Saudi Arabian hospital (March–August 2025). Methodological triangulation integrated semi-structured interviews with staff nurses (<i>n</i> = 26), nurse managers (<i>n</i> = 7), and quality officers (<i>n</i> = 2) (total <i>N</i> = 35), four non-managerial focus groups, and organisational document review. Analysis used a hybrid thematic approach guided by an integrated theoretical framework (Destructive Leadership, Theory of Planned Behavior, and Structure–Process–Outcome).</p> Results <p>Four interlocking themes emerged. Toxic leadership behaviours, including public humiliation/blame, intimidation, information gatekeeping, and perceived favouritism, were described as eroding psychological safety. These behaviours were perceived to constrain adverse-event reporting through concerns about retaliation, normalised concealment, and perceived futility linked to weak feedback loops and procedural filtering. Care quality was consequently perceived to be affected by defensive practice patterns, communication hesitation and delayed escalation, siloed teamwork, and reduced organisational learning. Hierarchical deference norms, weak accountability, and differential vulnerability among expatriate staff intensified these dynamics.</p> Conclusions <p>In this high power-distance setting, toxic nurse-manager leadership was perceived to contribute to a mutually reinforcing cycle of reporting suppression and silence that constrained reporting and was linked to perceived deterioration in care processes. Technical reporting infrastructures alone may be insufficient when psychological safety and leadership accountability are weak.</p> Implications for practice <p>Safety interventions should couple protected reporting pathways with robust leadership accountability and transparent feedback loops. Accreditation bodies may consider incorporating leadership climate and psychological safety as leading indicators alongside traditional patient safety metrics.</p> Clinical trial number <p>Not applicable.</p>