Addison’s disease is a rare condition, which world-wide, may affect many millions of people. In pregnancy however, it has been rarely reported and, in this setting, remains poorly understood. What we do know, is that it is an endocrine disorder characterized by adrenal insufficiency leading to decreased production of cortical hormones including most notably, cortisol, but also the androgens and aldosterone. The sequaelae may be varied but most significantly, can lead to a loss of the body’s normal resilience to stress and injury. We present the case of a 35-year-old woman who presented in late pregnancy with signs and symptoms of fulminating pre-eclampsia (PET). Paradoxically, she was found to have electrolyte abnormalities which persisted despite appropriate treatment. These were suggestive of an underlying endocrine disorder and she was subsequently diagnosed with atypical Addison’s disease. With appropriate management, she was stabilized and delivered safely. We report this as a rare example of newly diagnosed Addison’s disease discovered for the first time in late pregnancy. It highlights that although rarely diagnosed, early identification can help avoid potentially life-threatening sequalae such as acute adrenal insufficiency as well as complications including preterm birth, neonatal hypoglycaemia and prolonged hospital admission. This calls for ongoing vigilance in clinical care, and the continuous improvement of shared knowledge through collaborative communication and awareness of evidence based, best practice guidelines.