Immune checkpoint inhibitors have been incorporated into the treatment of various malignancies. An increasing body of literature is reporting rare but potentially fatal adverse events associated with these agents. In this case series, the authors report the clinical features and outcomes of seven patients who received immune checkpoint inhibitors for different solid organ malignancies and developed a tetrad of immune-related myocarditis, myositis, myasthenia gravis and transaminitis. Herein the authors review the literature and describe the current diagnostic and management approach for this overlapping syndrome. The authors' series highlights the importance of a high index of clinical suspicion, prompt comprehensive investigations, early multidisciplinary team involvement and initiation of immunosuppressive therapy when immune-related adverse events are suspected.